Perhaps you should try some spelling variations:
christian unity » christian laity, christian divinity, christian charity
bief history » brief history, brief hystory, ref history
reef history » brief history, reeves history, reef fishery
20th century » 18th century
2.1 germany » 21 germany, 2017 germany, 9.13 germany
imf history » brief history
2f germany » 2 germany, 20 germany, 21 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: %((christian unity) OR (christian union)) conversations %((2f germany) OR (2.1 germany)) %((imf history) OR (((bief history) OR (reef history)))) %2f 20th century%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((christian unity) OR (christian union)) conversations %((2f germany) or (2.1 germany)) %((imf history) or (((bief history) or (reef history)))) %2f 20th century%22".
• Adding a wildcard symbol may retrieve word variants: %((christian unity) OR (christian union)) conversations %((2f germany) or (2.1 germany)) %((imf history) or (((bief history) or (reef history)))) %2f 20th century%22*.