Perhaps you should try some spelling variations:
ghana health » china health, data health
health gain » health goals
hyoung tan » hyoung gun, young man, hong tan
yan ghana » yan guan, yan zhang
yang mind » yang cindy, yang jin, sang minh
chan ming » chan eng, chan fong, chan kang
wang » wing, lang

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (wang or wan) yan ghana health gain ((yang mind) or (((chan ming) OR (kian ming)))) hyoung tan ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (wang OR wan) yan ghana health gain ((yang mind) OR (((chan ming) OR (kian ming)))) hyoung tan ;.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(wang or wan) yan ghana health gain ((yang mind) or (((chan ming) OR (kian ming)))) hyoung tan ;".
• Adding a wildcard symbol may retrieve word variants: (wang or wan) yan ghana health gain ((yang mind) or (((chan ming) OR (kian ming)))) hyoung tan ;*.