Perhaps you should try some spelling variations:
great conversations » agent conversations, chat conversations, creative conversations
brief hystory » brief herstory, brief story, bief history
ref history » reef history, bief history, imf history
21 germany » 11 germany, 2 germany, 20 germany
%christianity » %christian

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: %christianity great conversations %21 germany %((ref history) OR (((brief hystory) OR (brief history)))) %2.2 ((20th century) OR (18th century))%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%christianity great conversations %21 germany %((ref history) or (((brief hystory) or (brief history)))) %2.2 ((20th century) OR (18th century))%22".
• Adding a wildcard symbol may retrieve word variants: %christianity great conversations %21 germany %((ref history) or (((brief hystory) or (brief history)))) %2.2 ((20th century) OR (18th century))%22*.