Perhaps you should try some spelling variations:
1918 germany » 8 germany
20th century » 18th century
20 germany » 2 germany, 8 germany, 5 germany
2f history » 2.1 history, imf history, etf history
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 %((20 germany) OR (((1918 germany) OR (7 germany)))) %2f history %2f 20th century%22.
• Adding a wildcard symbol may retrieve word variants: %22agriculture and state %((20 germany) or (((1918 germany) or (7 germany)))) %2f history %2f 20th century%22*.