Perhaps you should try some spelling variations:
when conversations » open conversations, agent conversations, chain conversations
win conversations » wine conversation, wins conversation, chain conversations
20th century » 18th century
etf history » reef history, ref history, tnf history
imf history » brief 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)) %7 germany %((etf 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)) %7 germany %((etf history) or (imf history)) %2f 20th century%22*".