Perhaps you should try some spelling variations:
reef history » brief history, reeves history, reef fishery
tnf history » etf history, ref history, motif history
imf history » brief history
2020 20th » 2020 16th, 2020 5th, 2020 4th
2 german » 3 german, 5 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 %((((reef history) OR (tnf history))) OR (imf history)) %((2020 20th) OR (2020 2021)) century%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22agriculture and state %2 german %((((reef history) or (tnf history))) or (imf history)) %((2020 20th) OR (2020 2021)) century%22".
• Adding a wildcard symbol may retrieve word variants: %22agriculture and state %2 german %((((reef history) or (tnf history))) or (imf history)) %((2020 20th) OR (2020 2021)) century%22*.