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