Perhaps you should try some spelling variations:
cheng ming » cheng bing, cheng ling, chen ping
weng fang » jing fang
chen wang » chen yang, chen rong, chen ping
john song » john wong, john bonn, john ngosong
wen wang » wei wang, men want, von wang
wan ren » wan wen, wan sern
shin » skin, sein, thin

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: wan ren ((weng fang) OR (wen wang)) ((cheng ming) OR (chen wang)) john song shin ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wan ren ((weng fang) OR (wen wang)) ((cheng ming) or (chen wang)) john song shin ;~".
• Adding a wildcard symbol may retrieve word variants: wan ren ((weng fang) OR (wen wang)) ((cheng ming) or (chen wang)) john song shin ;*.