They are - you simply have to do the extra bit of indexing work yourself.
Create a high level topic for each note, and put that in the front of the notebook, with a page number. Once you're beyond one book, keep a separate index book and update it periodically with a book/page number from the indexes in the individual books.
If you find yourself referring to a particular topic frequently, take some time and re-write the entry. That way you can correlate several writings on the topic, and add both a better framing and lessons learned.
I would argue that anything you refer back to even once should be translated into digital. Note I said translated, not transcribed. When converting to digital you should fix things: check the facts, make the diagrams pretty, fix the grammar.
Paper is great for a rough draft. Rewriting your rough draft to the final is always good practice.
agreed. the main thing i use pencil & paper for is sketching out designs for some physical stuff I make. I always start on paper, but if it's a design I'm actually going to use more than once, it gets drawn up on the computer.
Create a high level topic for each note, and put that in the front of the notebook, with a page number. Once you're beyond one book, keep a separate index book and update it periodically with a book/page number from the indexes in the individual books.
If you find yourself referring to a particular topic frequently, take some time and re-write the entry. That way you can correlate several writings on the topic, and add both a better framing and lessons learned.
It's a bit of extra work, but it's worth it.