Perhaps you should try some spelling variations:
yang yang » wang yan
wang yang » wang yan, wang liang, wang yanling
gene yang » gene bank
yang min » yang mind, yang jin, tang min
hong hai » shang hai, zhong tai, dang hai
a gene » a genre, a gender, a gentle
a a » a la
tan » than

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((yang yang) or (wang yang)) a a gene yang min ((hong hai) or (hong tan)) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((yang yang) OR (wang yang)) a a gene yang min ((hong hai) OR (hong tan)) ;.
• Adding a wildcard symbol may retrieve word variants: ((yang yang) or (wang yang)) a a gene yang min ((hong hai) or (hong tan)) ;*.