Perhaps you should try some spelling variations:
wang yuhan » wang luhang, wang yidan, fang yuan
guan cheng » yuan cheng, huang cheng, tan cheng
cheng chan » cheung chan, cheng han, cheng zhang
chan dang » chan kang, chan eng, chan fong
dang hung » dang cuong, fung hung, ming hung
yan guan » gan guan, yan yuan, yang guang
hung hai » hong hai, shang hai, dang hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((wang yuhan) or (wang yan)) yan guan cheng chan dang hung hai ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((wang yuhan) OR (wang yan)) yan guan cheng chan dang hung hai ;.
• Adding a wildcard symbol may retrieve word variants: ((wang yuhan) or (wang yan)) yan guan cheng chan dang hung hai ;*.