Perhaps you should try some spelling variations:
20th century » 18th century
2.1 germany » 21 germany, 2017 germany, 9.13 germany
tnf history » imf history, ref history, motif history
etf history » reef history, imf history, ref history
2f history » imf history, ref history, 7 history
2 germany » 7 germany, 2 german, 8 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 (2.1 germany)) %((((2f history) OR (tnf 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 (2.1 germany)) %((((2f history) OR (tnf history))) or (etf history)) %2f 20th century%22".
• Adding a wildcard symbol may retrieve word variants: %22agriculture and state %((2 germany) or (2.1 germany)) %((((2f history) OR (tnf history))) or (etf history)) %2f 20th century%22*.