Perhaps you should try some spelling variations:
dong huang » dong hoang, dang hung, dong hua
huang yang » huang ying, huang chang, wang yang
human gene » human genome, human gender, human bone
hong shu » cong shu, tong shui, wong shiu
wang ma » wang hua, wang yan, wang ban
ma hong » a hong, kia hong, tan hong
a gene » a genre, a gender, a gentle

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

• Performing a fuzzy search may retrieve terms with similar spellings: dong huang yang ((human gene) or (a gene)) wang ma hong shu ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: dong huang yang ((human gene) OR (a gene)) wang ma hong shu ;*.