I've been using Subsonic years ago and was really happy to discover it's available as a package for Synology (which I use). I immediately opted for Subsonic Premium

Installation was a breeze and most things work as expected, however I feel the search function (*the* core feature of Subsonic) is buggy. I always get a predefined set of 10 or so results and can click "More Song" which adds another 10 results but after that, the search is over. I've several search terms where there are considerably more songs containing the search tags in either filename or ID3 tag, but those won't show up in the search.
For example:
I do have a folder containing roughly 40 songs with "My Mashup Edit" in ID3. If I open this folder in the web interface, all songs and tags show up correctly.
Searching for "Mashup" in Subsonic search (web interface and Android app) yields only about 15 songs from this folder and some songs containing "Mashup" in other, random folders. No more results show up, I already clicked "Show more songs".
Then again, when I search more precisely "Mashup Edit", almost all of those 30 songs show up which leads me to believe the indexing has gone OK.
My question now is: Does Subsonic have some sort of limitation regarding the # of search results displayed (at least on Synology) or is there another way (like search operators or s.th.) to use?
I couldn't find an answer so far.
Any help would be greatly appreciated!
Sam