Perhaps you should try some spelling variations:
1918 germany » 8 germany
20th century » 18th century
2.1 germany » 21 germany, 2017 germany, 9.13 germany
ref history » reef history, brief history, bief history
11 germany » 11 german, 8 germany, 5 germany
2 germany » 2 german, 8 germany, 5 germany
20 20th » 90 20th, 2019 20th, 2020 20th

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: %22agriculture AND state %((((((11 germany) OR (1918 germany))) OR (2.1 germany))) OR (((2 germany) OR (7 germany)))) %ref history %20 20th century%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22agriculture and state %((((((11 germany) OR (1918 germany))) or (2.1 germany))) or (((2 germany) or (7 germany)))) %ref history %20 20th century%22".
• Adding a wildcard symbol may retrieve word variants: %22agriculture and state %((((((11 germany) OR (1918 germany))) or (2.1 germany))) or (((2 germany) or (7 germany)))) %ref history %20 20th century%22*.