Perhaps you should try some spelling variations:
among patients » among nations
bond patients » burned patients, bond ratings, bat patients
among breast » among east, facing breast, among forest
yang yang » wang yang, wang yan
yang jun » yang jui, pang jun, yang jin
wang » wing, wan, lang

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 yanling ((yang jun) OR (yang yang)) ((bond patients) OR (among patients)) risk among breast ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang yanling ((yang jun) or (yang yang)) ((bond patients) OR (among patients)) risk among breast ;~".
• Adding a wildcard symbol may retrieve word variants: wang yanling ((yang jun) or (yang yang)) ((bond patients) OR (among patients)) risk among breast ;*.