I know this unicode stuff is a pain in the ass but sometimes you need it
If a search string contains non-ascii characters (like german umlauts ä, ö, ü) you can't
search for it - you will always get a "No results found for query" message - at least I do.
Screenshot
I've tried to search for "Männer".
If the subject contains other restrictive keywords it isn't a real problem, but sometimes
it doesn't.