It is SO hard to find books I previously purchased and accidentally deleted from my library. There is NO place where stupid Google stores alll purchased media (there's a list of purchases in the play store account settings but all you needed to provide was a simple option to ADD the media back to Library... not the play store library, the library within the specific app for that kind of media (Google play BOOKS library, for books, and GOOGLE PLAY movies and TV, for movies and TV shows)