Perhaps you should try some spelling variations:
22christian union » christian union, christian upon
christian unity » christian union, christian laity, christian divinity
reef history » brief history, reeves history, reef fishery
ref history » brief history, bief history, imf history
20 germany » 7 germany, 8 germany, 5 germany
2 germany » 7 germany, 2 german, 8 germany

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: %((22christian union) OR (christian unity)) conversations %((2 germany) OR (20 germany)) %((reef history) OR (ref history)) %2f 18th century%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((22christian union) OR (christian unity)) conversations %((2 germany) or (20 germany)) %((reef history) or (ref history)) %2f 18th century%22".
• Adding a wildcard symbol may retrieve word variants: %((22christian union) OR (christian unity)) conversations %((2 germany) or (20 germany)) %((reef history) or (ref history)) %2f 18th century%22*.