Perhaps you should try some spelling variations:
select patients » cleft patients, selecting patient, benefit patients
patients risk » patient risk, patients links, patients si
wang yang » wang yan, wang liang, wang yanling
tong shui » tong hui, gong hui
tying up » taking up, tying _
pang jun » yang jui

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

• Performing a fuzzy search may retrieve terms with similar spellings: wang yang ((tying up) or (pang jun)) select patients risk ((tong shui) OR (cong shu)) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: wang yang ((tying up) OR (pang jun)) select patients risk ((tong shui) OR (cong shu)) ;.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang yang ((tying up) or (pang jun)) select patients risk ((tong shui) OR (cong shu)) ;".
• Adding a wildcard symbol may retrieve word variants: wang yang ((tying up) or (pang jun)) select patients risk ((tong shui) OR (cong shu)) ;*.