Perhaps you should try some spelling variations:
cheng zhang » cheng han, zhen zhang, chen zheng
china zhang » china chang, chin chang, china han
wang yuhan » wang luhang, wang yan, wang yidan
wei liang » wei qiang, wee liang, wei shang
liang sun » liang dan, liang tan, wing sun
lang a » lang 3, lang _

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: wang yuhan ((lang a) OR (erlang a)) ((china zhang) OR (cheng zhang)) wei liang sun ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang yuhan ((lang a) or (erlang a)) ((china zhang) OR (cheng zhang)) wei liang sun ;~".
• Adding a wildcard symbol may retrieve word variants: wang yuhan ((lang a) or (erlang a)) ((china zhang) OR (cheng zhang)) wei liang sun ;*.