Perhaps you should try some spelling variations:
curious conversations » curious conversion, courageous conversations, conscious conversations
serious conversation » serious conideration, versus conversation, ingenious conversation
reef history » brief history, reeves history, reef fishery
etf history » imf history, ref history, tnf history
20 germany » 2 germany, 7 germany, 8 germany
21 germany » 2.1 germany, 11 germany, 2 germany

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: %22christian ((curious conversations) OR (serious conversation)) %((20 germany) OR (21 germany)) %((etf history) OR (reef history)) %2f 18th century%22*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22christian ((curious conversations) OR (serious conversation)) %((20 germany) or (21 germany)) %((etf history) or (reef history)) %2f 18th century%22*".