Perhaps you should try some spelling variations:
patients risk » patient risk, patients links, patients si
cost patients » cost patient, cleft patients, care patients
risk tong » risk among, risk along
tong shui » tong hui, cong shu, gong hui
yang jui » yang judy, yang di, yang yi
yang up » tying up, yang jun, hang ups
yang xi » yang di, yang yi

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: (wan OR wing) yanling ((((yang up) OR (yang jui))) OR (yang xi)) cost patients risk tong shui ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(wan or wing) yanling ((((yang up) OR (yang jui))) or (yang xi)) cost patients risk tong shui ;~".
• Adding a wildcard symbol may retrieve word variants: (wan or wing) yanling ((((yang up) OR (yang jui))) or (yang xi)) cost patients risk tong shui ;*.