Perhaps you should try some spelling variations:
yuan cheng » yuan chang, huang cheng, yu cheng
than china » tuan china, han china, wuhan china
yuan wang » yan wang, yuan kang, yuan chang
ren yang » chen yang, dan yang, pei yang
wei wang » wei yang, wen wang, wei shang
wang yue » wong yue, wang hua, wang yan

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: ((yuan wang) OR (yuan cheng)) than china ((ren yang) OR (ren yan)) wei wang yue ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((yuan wang) or (yuan cheng)) than china ((ren yang) OR (ren yan)) wei wang yue ;~".
• Adding a wildcard symbol may retrieve word variants: ((yuan wang) or (yuan cheng)) than china ((ren yang) OR (ren yan)) wei wang yue ;*.