Perhaps you should try some spelling variations:
21 germany » 11 germany, 2 germany, 20 germany
2f history » imf history, etf history, ref history
2 german » 3 german, 5 german
2.2 20th » 2020 20th, 2023 20th, 2021 20th
2f 20th » 20 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 %((2 german) OR (21 germany)) %2f history %((2f 20th) OR (2.2 20th)) century%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22agriculture and state %((2 german) or (21 germany)) %2f history %((2f 20th) OR (2.2 20th)) century%22".
• Adding a wildcard symbol may retrieve word variants: %22agriculture and state %((2 german) or (21 germany)) %2f history %((2f 20th) OR (2.2 20th)) century%22*.