Perhaps you should try some spelling variations:
christians upon » christians among, christians from, christians being
christian upon » christianity upon, christ upon, christian u
20th century » 18th century
2.1 germany » 2017 germany, 9.13 germany, 9.14 germany
ref history » reef history, brief history, bief history
imf history » brief history
21 germany » 11 germany, 2 germany, 20 germany
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: %((((christian upon) OR (christians upon))) OR (christian union)) conversations %((21 germany) OR (2.1 germany)) %((ref history) OR (imf history)) %2f 20th century%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((((christian upon) OR (christians upon))) or (christian union)) conversations %((21 germany) or (2.1 germany)) %((ref history) or (imf history)) %2f 20th century%22".
• Adding a wildcard symbol may retrieve word variants: %((((christian upon) OR (christians upon))) or (christian union)) conversations %((21 germany) or (2.1 germany)) %((ref history) or (imf history)) %2f 20th century%22*.