Perhaps you should try some spelling variations:
black david » brock david, blanc david, baldock david
bank david » bank ravi, park david
mark david » mare davide, parker david
tang tang » taizong tang
tang yang » wang yang, yang yang, tan yang
yang 1 » yang _, yang 8, yang 4
1 gene » 11 gene, a1 gene, l1 gene
choi » chi, cho

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: tang tang yang 1 gene ((((bank david) OR (black david))) OR (mark david)) young choi ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tang tang yang 1 gene ((((bank david) OR (black david))) or (mark david)) young choi ;~".
• Adding a wildcard symbol may retrieve word variants: tang tang yang 1 gene ((((bank david) OR (black david))) or (mark david)) young choi ;*.