You might be seeing fake files. They're common for music & video, I guess it's just as likely that other file types are effected too. Do they sit connecting for a long time before needing more sources? There's info in the sticky below
Fake files showing up in search results

You might also find some tips for searching etc in the audiobooks sub-forum here
https://www.gnutellaforums.com/audiobook-karaoke-issues/