Perhaps you should try some spelling variations:
20th century » 18th century
etf history » reef history, imf history, ref history
2.1 germany » 2017 germany, 9.13 germany, 9.14 germany
21 germany » 11 germany, 2 germany, 20 germany
2f history » imf history, ref history, tnf history
2f germany » 2 germany, 20 germany, 25 germany
8 germany » 7 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 %((((((2f germany) OR (21 germany))) OR (((8 germany) OR (1918 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 %((((((2f germany) OR (21 germany))) or (((8 germany) or (1918 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 %((((((2f germany) OR (21 germany))) or (((8 germany) or (1918 germany))))) or (2.1 germany)) %((2f history) or (etf history)) %2f 20th century%22*.