Perhaps you should try some spelling variations:
china health » china's health, child health, capita health
gain sharing » basin sharing, chain sharing, fair sharing
yan china » can china, dan china, han china
gain sang » shin sang
amin hong » among hong, tin hong, asia hong
min hong » tin hong, min hyoung, min jeong
wang » wing, wan, lang
tan » than

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 yan china health ((gain sang) OR (gain sharing)) ((min hong) OR (amin hong)) tan ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang yan china health ((gain sang) or (gain sharing)) ((min hong) OR (amin hong)) tan ;~".
• Adding a wildcard symbol may retrieve word variants: wang yan china health ((gain sang) or (gain sharing)) ((min hong) OR (amin hong)) tan ;*.