Perhaps you should try some spelling variations:
yuhan kang » chan kang, yuhuan huang
yang ping » yang jing, yang liang, yang using
ping wang » ping pong, hong wang
yuan kang » yuan wang, yuan chang, chan kang
kang hay » eang hay, kang han, dang hai
yang xi » yang di, yang jui
yang yi » yang di, yang jui

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: yang ping wang ((yuhan kang) OR (yuan kang)) ((yang xi) OR (yang yi)) kang hay ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "yang ping wang ((yuhan kang) OR (yuan kang)) ((yang xi) or (yang yi)) kang hay ;~".
• Adding a wildcard symbol may retrieve word variants: yang ping wang ((yuhan kang) OR (yuan kang)) ((yang xi) or (yang yi)) kang hay ;*.