Perhaps you should try some spelling variations:
tnf history » etf history, ref history, motif history
imf history » brief history
2f history » etf history, ref history, 7 history
2 german » 3 german
5 german » 3 german

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 german) OR (5 german)) %((((2f history) OR (tnf history))) OR (imf history)) %2f ((20th century) OR (18th century))%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22agriculture and state %((2 german) OR (5 german)) %((((2f history) or (tnf history))) or (imf history)) %2f ((20th century) or (18th century))%22".
• Adding a wildcard symbol may retrieve word variants: %22agriculture and state %((2 german) OR (5 german)) %((((2f history) or (tnf history))) or (imf history)) %2f ((20th century) or (18th century))%22*.