Perhaps you should try some spelling variations:
patients risk » patient risk, patients links, patients si
among peers » among ers, among users, among letters
tan yang » tan ying, tan yong, tao yang
dan yang » daun yang, wang yang, yang yang
can post » can cost, can past, can postal
can lost » can cost, can lose, can boost

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 ((tan yang) OR (dan yang)) ((can post) OR (can lost)) patients risk among peers ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang ((tan yang) OR (dan yang)) ((can post) or (can lost)) patients risk among peers ;~".
• Adding a wildcard symbol may retrieve word variants: wang ((tan yang) OR (dan yang)) ((can post) or (can lost)) patients risk among peers ;*.