Perhaps you should try some spelling variations:
christian upon » christians upon, christianity upon, christ upon
24th century » 20th century, 14th century, 21th century
2.1 germany » 2017 germany, 9.13 germany, 9.14 germany
ref history » reef history, brief history, bief history
21 germany » 11 germany, 2 germany, 20 germany
2021 24th » 2021 4th, 2021 6th, 2021 7th

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 upon) OR (christian union)) conversations %((21 germany) OR (2.1 germany)) %ref history %2021 24th century%22.
• Adding a wildcard symbol may retrieve word variants: %((christian upon) or (christian union)) conversations %((21 germany) or (2.1 germany)) %ref history %2021 24th century%22*.