I added a term to the glossary (not case-sensitive):
Dust bin;Dust bins;Dustbin;Dustbins
This is to catch the most important variants (and yes, singular and plural, as the German term is the same for both).
But here it does not trigger:
The Glossaries search with Ctrl-Shift-F10 finds the term.
Changing the order to
Dustbin;Dustbins;Dust bin;Dust bins
I do not see any explaination for this. And I assume this should not be the case.