Perhaps you should try some spelling variations:
curious conversations » curious conversion, serious conversation, courageous conversations
design conclusions » design conclusion
ref history » reef history, brief history, bief history
21 germany » 11 germany, 2 germany, 20 germany
20 18th » 2017 18th, 2021 18th, 2018 18th

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 ((curious conversations) OR (design conclusions)) %21 germany %ref history %20 18th century%22.
• Adding a wildcard symbol may retrieve word variants: %22christian ((curious conversations) or (design conclusions)) %21 germany %ref history %20 18th century%22*.