Perhaps you should try some spelling variations:
content conversations » content conservation, center conversations, content conversion
open conversations » agent conversations, roman conversations, honest conversations
reef history » brief history, reeves history, reef fishery
bief history » brief history, brief hystory, imf history
21 germany » 11 germany, 2 germany, 20 germany

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: %christian ((open conversations) OR (content conversations)) %21 germany %((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: "%christian ((open conversations) OR (content conversations)) %21 germany %((reef history) or (bief history)) %2.2 ((20th century) or (18th century))%22".
• Adding a wildcard symbol may retrieve word variants: %christian ((open conversations) OR (content conversations)) %21 germany %((reef history) or (bief history)) %2.2 ((20th century) or (18th century))%22*.