Perhaps you should try some spelling variations:
ghana health » data health
china health » china's health, child health, capita health
hyoung tan » hyoung gun, young man, hong tan
song ming » song bing, song min, gong min
lang yan » wang yan, wang yang, zhang yan
sang min » sang minh, song min, tang min

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 ((ghana health) or (china health)) goals ((sang min) or (song ming)) hyoung tan ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: lang yan ((ghana health) OR (china health)) goals ((sang min) OR (song ming)) hyoung tan ;.
• Adding a wildcard symbol may retrieve word variants: lang yan ((ghana health) or (china health)) goals ((sang min) or (song ming)) hyoung tan ;*.