Perhaps you should try some spelling variations:
2.1 germany » 2017 germany, 9.13 germany, 9.14 germany
21 germany » 11 germany, 2 germany, 20 germany
2f history » 2.1 history, imf history, etf history
20 20th » 2019 20th, 2020 20th, 2023 20th
90 20th » 94 20th, 1990 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 %((21 germany) OR (2.1 germany)) %2f history %((20 20th) OR (((90 20th) OR (94 4th)))) century%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22agriculture and state %((21 germany) OR (2.1 germany)) %2f history %((20 20th) or (((90 20th) or (94 4th)))) century%22".
• Adding a wildcard symbol may retrieve word variants: %22agriculture and state %((21 germany) OR (2.1 germany)) %2f history %((20 20th) or (((90 20th) or (94 4th)))) century%22*.