Perhaps you should try some spelling variations:
cheng zhang » cheng han, zhen zhang, chen zheng
china zhang » china chang, chin chang, china han
wang kyoung » wang hyoung, hwang byoung, wang yong
kyoung yun » young yun, kyoung yang, hyoung gun
fan sheng » fang sheng, qian sheng, han shen
yang jie » yang jin, yang di, yang jui
yan je » han je

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: fan sheng ((yan je) OR (yang jie)) ((china zhang) OR (cheng zhang)) wang kyoung yun ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fan sheng ((yan je) or (yang jie)) ((china zhang) OR (cheng zhang)) wang kyoung yun ;~".
• Adding a wildcard symbol may retrieve word variants: fan sheng ((yan je) or (yang jie)) ((china zhang) OR (cheng zhang)) wang kyoung yun ;*.