Perhaps you should try some spelling variations:
yuan cheng » yuan chang, huang cheng, yu cheng
cheng yan » cheng han, cheng guan, chen yang
wang yong » wang hyoung, wang yan, wang shiyong
wang yang » wang yan, wang liang, wang yanling
kong saur » kong sar, kong siu, kong your
yan yuan » yan guan, fang yuan, nan 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: yan yuan cheng yan ((wang yong) OR (wang yang)) jin ((cong shu) OR (kong saur)) ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "yan yuan cheng yan ((wang yong) OR (wang yang)) jin ((cong shu) or (kong saur)) ;~".
• Adding a wildcard symbol may retrieve word variants: yan yuan cheng yan ((wang yong) OR (wang yang)) jin ((cong shu) or (kong saur)) ;*.