Perhaps you should try some spelling variations:
yang yang » wang yang, wang yan
dong nan » dong yang, dong sin, dong bin
dong cao » dong xiao, dan cao, yong cai
gene yan » gene bank, ren yan, see yan
jiu cong » li cong
yan jiu » yang jie, yang jin, pang jiu
a gene » a genre, a gender, a gentle
ya a » a a, y a, ye a

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((((dong nan) or (dong cao))) or (yang yang)) ya a gene yan jiu cong shu ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((dong nan) OR (dong cao))) OR (yang yang)) ya a gene yan jiu cong shu ;.
• Adding a wildcard symbol may retrieve word variants: ((((dong nan) or (dong cao))) or (yang yang)) ya a gene yan jiu cong shu ;*.