Semantic search finds notes by what they say rather than the exact words in them. It is part of the Pro and Lifetime plans and it runs on the note index.
Turning it on in a search
Open search as usual and tap the sparkle toggle in the search field. The placeholder changes to searching with AI, and unlike keyword search, it runs when you submit rather than as you type. Results come back as a ranked list of the closest matches.
What that changes
Search for the pricing thing we argued about and the right note comes back even if it says margin discussion and never uses the word pricing. You do not have to remember your own phrasing, which is the part most people are bad at. Locked notes are not in the index and never come back here.
When keyword search is still better
If you know an exact term, a name or a code, the normal search is faster and exact, and it also finds the words inside the PDFs in your notes, which search by meaning does not look at. The sparkle toggle is for when you remember the meaning, not the words.
If results look thin
On desktop the sparkle toggle only appears once an indexing model is enabled in Settings under Models. New notes take a moment to index, and a fresh import takes longer, so give the index time to finish before judging results. The Indexing tab in Settings shows the progress.