Perhaps you should try some spelling variations:
longo john » wong john
kong john » king john, wong john, wrong john
yan xuan » yan guan, yan yuan, wang xuan
xuan hua » tuan hua, xuan thuy, tan hua
hua chen » jui chen, yu chen, a chen
wong sam » wong sau, wong lai, von sam
wang » wing, wan, lang
sar » sara, star, saur

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 yan xuan hua chen ((kong john) OR (longo john)) ((wong sam) OR (kong sar)) ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang yan xuan hua chen ((kong john) OR (longo john)) ((wong sam) or (kong sar)) ;~".
• Adding a wildcard symbol may retrieve word variants: wang yan xuan hua chen ((kong john) OR (longo john)) ((wong sam) or (kong sar)) ;*.