I use Thunderbird every day, and I agree with you.
If they want to kill some low-hanging fruit, search is fundamentally broken. I've almost never found what I'm searching for -- it's reddit bad. It's usually better for me just to go log into that gmail account and search from there.
Really? I don't remember having any major problems with search recently. Search is a few orders of magnitude better than the junk mail classification, at least for me. I don't know what algorithms they use for junk classification, but here are some observations:
1) I mark 100% of the emails from a particular sender or with a particular subject line as junk, yet the junk classifier still puts emails from that sender or with that subject in my inbox. This is the low-hanging fruit -- the stuff that is so obvious that it is spam that a human can figure it out without looking at the message body at all, yet Thunderbird can't seem to get it right no matter how much you train it. I can only guess that they are placing too much weight on the body content (which is easily padded with hidden text to con the algorithm) when a bad sender/subject should trump whatever is in the body.
2) Emails from people that I've emailed in the past sometimes end up in the junk folder. I thought they were supposed to be whitelisted automatically (by automatically being appended to some special section of your address book).
3) I've implemented message filters to detect certain words like our product name and move the incoming message to a high-priority folder, yet messages that should match the filter still end up in the junk folder on rare occasions (and, yes, I have it configured to run the filter before junk classification is applied -- I'm assuming that junk classification should not be applied if a filter moves the message out of the inbox).
4) It sometimes seems to just stop learning, so I have to reset and retrain the junk classifier or it gets to the point where the only emails that it recognizes as being junk are the ones in a foreign language.
Yeah, search is a huge mess. For example, I'm out looking for houses and I've gotten a bunch of notices in the past couple weeks for open houses. I search for "open house" and not a single result it presented was for any of the emails I've previously received. In fact none of the emails it returned seemed to have either "open" or "house" in them, I have no idea why it selected the emails it did.
Actually, I've developed a theory that the search actually uses a stochastic method that randomly samples emails from my mailboxes in the hopes that some of them will match my search result.
Assuming you're using the global search mechanism, a porter stemmer is used which means that the search engine sees all of "house", "houses", "housed", "housing", etc. the same.
The search also biases the results based on recency and things like whether the message has been starred/flagged, whether it was authored by/involves contacts in your address book, etc.
e15ctr0n is right that your best option is to use quotes to do a phrase search of "open house" in this situation, although you will still run afoul of the porter stemmer. (Unfortunately a post-pass filter if you realllly want "house" was never implemented. There is an open bug, however.)
No, I mean, I actually searched for "open house" in quotes. (I tried the terms without quotes as well, but when that first set of results turned up useless I tried the quotes).
The results were literally what I describe, just a random sample of emails from the last few years. I keep using the search hoping I get something useful returned, and even when I do things like put in exact phrases I know are in the message, I get a random pile of junk back.
I should just learn my lesson and stop trying to be honest.
I just did some tests using "Edit > Find > Search Messages" to search (I'm not sure what asutherland means by the "global search mechanism") and based on a few tests searching for "contains" matches on the body text here are my conclusions:
1) If you use quotes, it is looking for the quotes in the text, so I'm surprised you got any matches at all.
2) If you don't use quotes, it is still looking for an exact match (except that it's not case sensitive), so searching for "open house" without quotes should not match unless the words are adjacent to each other.
3) It doesn't seem to pay attention to token boundaries, so a search for "house" (without quotes) matches "warehouse"
So, it is a little unintuitive (and really should have a help button that explains exactly what it does), but it seems to work for me. I don't use IMAP, though, and the comments by qznc about IMAP [1] seem like they may explain why you are seeing what you are seeing if you use IMAP.
Edit: I just noticed e15ctr0n's link to info on the global search -- I don't have that enabled (probably disabled it to save disk space a long time ago) so if that's where you are seeing problems, that explains why I never noticed.
So for fun, I just sent myself an email with the subject "open house" and body "open house" (no quotes).
I then searched for "open house" (with quotes) and got a list back. Sorted by relevance, they return in the following chronological order: 2008, 2012, 2013x7, 2012x23, 2011x12, 2010x12 and on and on. Nothing from 2014 at all, and nothing from 2015 at all.
All of the returns have "open house" (or some variant) in them, quite a few have punctuation or non-alphanumeric characters right next to them, so that's cool. In quite a few "open houses" scores more highly than "open house".
So I filtered down to one mailbox. Now, I get a few from 2014, but no joy on my recent one.
I change the filter to another mailbox. About 10 down (there's only 12 "matching" in this mailbox) I see one of the relevant emails I was looking for earlier, but not the one I explicitly just sent myself.
If I remove all filter constraints and sort by date instead of relevance, the email I just sent shows up at the top, followed by some emails where "open houses" match my query, followed by the earlier email I was looking for.
So it's kinda working if I sort it by date. Sorting by relevance seems to be entirely useless. Sorting by mailbox is kinda useful, but doesn't seem to show most recent.
I dunno, it still seems faster and more accurate to hit each of my mailboxes separately from the web interfaces if I need to search them.
I think qznc might have hit the nail on the head about IMAP and getting weirdly out of sync.
1) It shows me two search fields and irritatingly I need them both. One is the global search in the index. The other searches linearly per folder without an index.
2) If you disable local caching for IMAP, it does not index the emails, so the global search reports nothing. (if you enable caching it regularly goes out of sync with the server and behaves weird)
3) Linear search through an email folder in 2015? It is slow, for full text search.
Altogether, no fast full text search in Thunderbird for me. Compare that to Gmail, where it works great.
Ugh, the search is the one part I find lacking. I use the 'quick filter' instead, which behaves like I want search to behave - quickly, and in the same window - whereas the 'search' results are presented in some bizarre order that has yet to 'just land me' at the results I want.
If they want to kill some low-hanging fruit, search is fundamentally broken. I've almost never found what I'm searching for -- it's reddit bad. It's usually better for me just to go log into that gmail account and search from there.