I want to ditch foobar2k but this is pretty much the only thing keeping me on it. In musicbee, if I start typing a word in the library, it will find the first thing based on the currently sorted album. For example, if I have my library sorted by album and type 'j-a-z', it'll stop at the first album entry for 'jazz album' and that's all. In foobar however, I can type 'j-a-z' and it will find the first song, artist or album containing those letters, even if its in the middle of the word, so I can type 'j-a-z-z' and have it land on 'jazz album', or I can type 'j-a-z-z-y' and have it highlight 'jazzy song' in 'other album'.
Its a very useful function that I use all the time. Very easy to find a specific song you want to hear and just have it shuffle into the rest of the library, unlike musicbee now where if you want to do this, you have to either change your whole sorting to search by title/artist/etc, type in an album and search through it to find the song you're looking for, or use the musicbee search to find it, then go back to the full library when you're done to listen to everything else.