Perhaps you should try some spelling variations:
20 germany » 2 germany, 8 germany, 5 germany
21 germany » 11 germany, 2 germany, 8 germany
2020 20th » 2020 16th, 2020 2021, 2020 6th
2020 4th » 2020 16th
2020 5th » 2020 16th

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 %((((20 germany) OR (7 germany))) OR (21 germany)) %brief history %((2020 20th) OR (((2020 4th) OR (2020 5th)))) century%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22agriculture and state %((((20 germany) OR (7 germany))) or (21 germany)) %brief history %((2020 20th) or (((2020 4th) or (2020 5th)))) century%22".
• Adding a wildcard symbol may retrieve word variants: %22agriculture and state %((((20 germany) OR (7 germany))) or (21 germany)) %brief history %((2020 20th) or (((2020 4th) or (2020 5th)))) century%22*.