Perhaps you should try some spelling variations:
2017 germany » 20 germany, 2006 germany, 21 germany
ref history » reef history, brief history, bief history
imf history » brief history
17 germany » 7 germany, 11 germany, 12 germany
13 bavaria » _ bavaria, ne bavaria, ii bavaria
%deaf » %leaf, %deal, %dean

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: %22jews %deaf education %((2017 germany) OR (17 germany)) %13 bavaria %((ref history) OR (imf history))%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22jews %deaf education %((2017 germany) OR (17 germany)) %13 bavaria %((ref history) or (imf history))%22".
• Adding a wildcard symbol may retrieve word variants: %22jews %deaf education %((2017 germany) OR (17 germany)) %13 bavaria %((ref history) or (imf history))%22*.