Perhaps you should try some spelling variations:
great conversations » agent conversations, chat conversations, creative conversations
reef history » brief history, reeves history, reef fishery
bief history » brief history, brief hystory, imf history
2.1 germany » 21 germany, 2017 germany, 9.13 germany
ref history » brief history, imf history, etf history
%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 %2.1 germany %((((ref history) OR (reef history))) OR (bief 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 %2.1 germany %((((ref history) OR (reef history))) or (bief history)) %2.2 ((20th century) or (18th century))%22".
• Adding a wildcard symbol may retrieve word variants: %christianity great conversations %2.1 germany %((((ref history) OR (reef history))) or (bief history)) %2.2 ((20th century) or (18th century))%22*.