How to find a book by its cover
You are not supposed to judge a book by its cover, but you are absolutely allowed to find one by it. Covers are designed to be memorable, which makes them unusually good search targets, even when all you hold is "dark green, gold lettering, maybe a bird".
Two situations, two methods: you can see the cover right now, or you only remember it.
Cover in front of you vs. cover in your head
If the cover is in front of you, on a train, in a video, in a shop window, capture it: a photo through Google Lens resolves most covers to the exact edition, and a photo shared to UnMiss comes back as the identified book. Partial covers work more often than you would expect; spines and even sprayed edges are distinctive in the current design era.
If the cover is only in your memory, translate it to words: dominant color, the object on it, the typography style, plus a genre guess, and add "book cover" to the search. Image results scan fast; your eye will catch it in a grid where a text list would fail. BookTok-famous covers also lurk in Goodreads lists and "books with green covers" roundups, which exist for exactly this reason.
From cover to shelf
Photograph or share it
Snap the physical cover, or share the post it appeared in. Send either to UnMiss from the share sheet.
Confirm the book
UnMiss names the book, with the standard published cover and author from Google Books; confirm with a tap.
Shelve it before it fades
The book lands on your TBR with its cover attached, so the next time it is "the green one", the green one is right there.
Questions
The cover I remember does not match the one in stores.
Editions change covers constantly, and BookTok special editions make it worse. Match on title and author, not art; the guide on TikTok books covers the edition maze.
Can I find it from just the spine?
Often: spines carry title, author and publisher mark. Photograph the shelf and zoom, or Lens the spine directly; series spines with distinctive design resolve especially well.
It was in the background of a photo, tiny. Worth trying?
Crop in and try Lens anyway; you will be surprised. Failing that, note whose photo it was; a person’s bookshelf is a better index than a search engine.