Perhaps you should try some spelling variations:
reef history » brief history, reeves history, reef fishery
imf history » brief history
11 germany » 11 german, 1918 germany, 7 germany
2019 20th » 2019 4th, 2019 6th, 2019 16th
2019 5th » 2019 4th, 2019 6th

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 %11 germany %((reef history) OR (imf history)) %((2019 20th) OR (2019 5th)) century%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22agriculture and state %11 germany %((reef history) or (imf history)) %((2019 20th) OR (2019 5th)) century%22".
• Adding a wildcard symbol may retrieve word variants: %22agriculture and state %11 germany %((reef history) or (imf history)) %((2019 20th) OR (2019 5th)) century%22*.