Perhaps you should try some spelling variations:
yuan cheng » yuan chang, huang cheng, yu cheng
cheng tan » cheng han, chen tan, cheng guan
tan hyung » tan hong, jay hyung, han heung
hyung kim » yong kim
dang hadi » dang hai
yan yuan » yan guan, fang yuan, nan yan
wai yan » wang yan, wei yang

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: wai yan yuan cheng tan hyung kim ((hong tan) or (dang hadi)) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: wai yan yuan cheng tan hyung kim ((hong tan) OR (dang hadi)) ;*.