Perhaps you should try some spelling variations:
cheng zhang » cheng han, zhen zhang, chen zheng
zhang minh » zhang ming, zhang xin, chang min
wang yang » wang yan, wang liang, wang yanling
yao yang » yang yang
xi cheng » _ cheng, yi chen, li chen
jeong su » jeong _, jeong mi, jeong 情
rong su » rong yu, cong sun, yong suk

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

• Performing a fuzzy search may retrieve terms with similar spellings: qian ((yao yang) or (wang yang)) xi cheng zhang minh ((rong su) OR (jeong su)) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: qian ((yao yang) OR (wang yang)) xi cheng zhang minh ((rong su) OR (jeong su)) ;*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "qian ((yao yang) or (wang yang)) xi cheng zhang minh ((rong su) OR (jeong su)) ;*".