Perhaps you should try some spelling variations:
when conversations » open conversations, agent conversations, chain conversations
win conversations » ai conversations, wine conversation, wins conversation
20th century » 18th century
2.1 germany » 2017 germany, 9.13 germany, 9.14 germany
imf history » brief history
21 germany » 11 germany, 2 germany, 25 germany
20 germany » 2 germany, 7 germany, 8 germany
2f history » 2.1 history, etf history, ref history
2f 20th » 20 20th, 2.2 20th

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 ((win conversations) OR (when conversations)) %((((21 germany) OR (20 germany))) OR (2.1 germany)) %((2f history) OR (imf history)) %2f 20th century%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22christian ((win conversations) OR (when conversations)) %((((21 germany) or (20 germany))) or (2.1 germany)) %((2f history) or (imf history)) %2f 20th century%22".
• Adding a wildcard symbol may retrieve word variants: %22christian ((win conversations) OR (when conversations)) %((((21 germany) or (20 germany))) or (2.1 germany)) %((2f history) or (imf history)) %2f 20th century%22*.