Perhaps you should try some spelling variations:
2f history » 2.1 history, imf history, etf history
20 germany » 2 germany, 7 germany, 8 germany
25 germany » 5 germany, 2 germany, 21 germany
2019 20th » 2019 6th, 2019 16th, 2019 7th
2019 5th » 2019 6th
90 20th » 20 20th, 1990 20th
94 20th » 4 20th, 94 24th, 1994 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 %((25 germany) OR (20 germany)) %2f history %((((2019 20th) OR (((2019 5th) OR (2019 4th))))) OR (((90 20th) OR (94 20th)))) century%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22agriculture and state %((25 germany) or (20 germany)) %2f history %((((2019 20th) or (((2019 5th) or (2019 4th))))) or (((90 20th) OR (94 20th)))) century%22".
• Adding a wildcard symbol may retrieve word variants: %22agriculture and state %((25 germany) or (20 germany)) %2f history %((((2019 20th) or (((2019 5th) or (2019 4th))))) or (((90 20th) OR (94 20th)))) century%22*.