Perhaps you should try some spelling variations:
unity conversations » union conversations, party conversations, city conversation
unit conversions » unit conversion, units conversion, _ conversions
reef history » brief history, reeves history, reef fishery
ref history » brief history, bief history, imf history
21 germany » 2 germany, 20 germany, 7 germany
11 germany » 11 german, 1918 germany, 7 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 ((unity conversations) OR (unit conversions)) %((21 germany) OR (11 germany)) %((ref history) OR (reef history)) %2023 ((20th century) OR (18th century))%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%christian ((unity conversations) OR (unit conversions)) %((21 germany) or (11 germany)) %((ref history) or (reef history)) %2023 ((20th century) or (18th century))%22".
• Adding a wildcard symbol may retrieve word variants: %christian ((unity conversations) OR (unit conversions)) %((21 germany) or (11 germany)) %((ref history) or (reef history)) %2023 ((20th century) or (18th century))%22*.