Perhaps you should try some spelling variations:
cost patients » cost patient, cleft patients, care patients
patients risk » patient risk, patients links, patients si
wang liang » wang yang
risk tong » risk among, risk along
pang jun » yang jui
tong hui » wang hui
yang up » yang jui, tying up, yang jun

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: wang liang ((yang up) or (pang jun)) cost patients risk tong hui ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: wang liang ((yang up) OR (pang jun)) cost patients risk tong hui ;*.