Perhaps you should try some spelling variations:
patients risk » patients links, patients si, patients view
wing yanling » wang yanling, wang yangming
patient risk » patient task, patient cost, orient risk
among hui » among heis, among eu, tong hui
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: wing yanling ((yang up) OR (yang xi)) care ((patients risk) OR (patient risk)) among hui ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wing yanling ((yang up) or (yang xi)) care ((patients risk) OR (patient risk)) among hui ;~".
• Adding a wildcard symbol may retrieve word variants: wing yanling ((yang up) or (yang xi)) care ((patients risk) OR (patient risk)) among hui ;*.