Perhaps you should try some spelling variations:
ghana health » china health, data health
health gain » health goals
young male » young males, young age
zhang yan » zhang fan, zhang jian, wang yan
sang minh » kang minah, anh minh, song min
chang min » zhang ming, chang mae, chan ming
lang yan » wang yan, wang yang, yang yang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((lang yan) OR (zhang yan)) ghana health gain ((sang minh) or (chang min)) young male ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((lang yan) OR (zhang yan)) ghana health gain ((sang minh) OR (chang min)) young male ;.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((lang yan) OR (zhang yan)) ghana health gain ((sang minh) or (chang min)) young male ;".
• Adding a wildcard symbol may retrieve word variants: ((lang yan) OR (zhang yan)) ghana health gain ((sang minh) or (chang min)) young male ;*.