Perhaps you should try some spelling variations:
design conclusions » design conclusion
win conversations » when conversations, ai conversations, ip conversations
ref history » reef history, brief history, bief history
21 germany » 11 germany, 2 germany, 20 germany

Try widening your search to All Fields.

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• If you are trying to use Boolean operators, they must be ALL CAPS: %22christian ((win conversations) OR (design conclusions)) %21 germany %ref history %20 ((20th century) OR (18th century))%22.
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