Perhaps you should try some spelling variations:
older patients » elderly patients
patients risk » patient risk, patients links, patients si
wang liang » wang yang
among shu » cong shu, among eu, among hr
among sex » among smes, among eu
yang up » yang jui, tying up, yang jun
yang xi » yang di, yang yi, yang jui

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 liang ((yang up) OR (yang xi)) older patients risk ((among shu) OR (among sex)) ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang liang ((yang up) or (yang xi)) older patients risk ((among shu) OR (among sex)) ;~".
• Adding a wildcard symbol may retrieve word variants: wang liang ((yang up) or (yang xi)) older patients risk ((among shu) OR (among sex)) ;*.