Perhaps you should try some spelling variations:
20th century » 18th century
2.1 germany » 21 germany, 2017 germany, 9.13 germany
etf history » reef history, imf history, ref history
2f history » 2.1 history, imf history, ref history
2 germany » 12 germany, 7 germany, 2 german
8 germany » 7 germany, 1918 germany
2f 20th » 20 20th, 2.2 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 germany) OR (8 germany))) OR (1((2 germany) OR (8 germany))))) OR (2.1 germany)) %((2f history) OR (etf history)) %2f 20th century%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22agriculture and state %((((((2 germany) OR (8 germany))) or (1((2 germany) OR (8 germany))))) or (2.1 germany)) %((2f history) or (etf history)) %2f 20th century%22".
• Adding a wildcard symbol may retrieve word variants: %22agriculture and state %((((((2 germany) OR (8 germany))) or (1((2 germany) OR (8 germany))))) or (2.1 germany)) %((2f history) or (etf history)) %2f 20th century%22*.