Perhaps you should try some spelling variations:
david young » david loundy
young child » young children
mark david » mare davide, parker david
zili gene » iii gene
gene mark » gene bank, gene part, nene marc
yan yang » yang yang, dan yang, tan yang
yao yang » yang yang
wang » wan

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: ((wang OR wing) OR lang) ((yan yang) OR (yao yang)) zili gene mark david young child ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((wang OR wing) or lang) ((yan yang) or (yao yang)) zili gene mark david young child ;~".
• Adding a wildcard symbol may retrieve word variants: ((wang OR wing) or lang) ((yan yang) or (yao yang)) zili gene mark david young child ;*.