Perhaps you should try some spelling variations:
burned patients » burnt patient, surgery patients
bond patients » among patients, bond ratings, bat patients
among east » among breast, among ers, among health
wang yang » wang yan, wang liang, wang yanling
yang jin » yang jie, yang jun, ying jin
yang fan » zhang fan, yang dean, yang yang

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 yang ((yang jin) OR (yang fan)) ((bond patients) OR (burned patients)) risk among east ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang yang ((yang jin) or (yang fan)) ((bond patients) OR (burned patients)) risk among east ;~".
• Adding a wildcard symbol may retrieve word variants: wang yang ((yang jin) or (yang fan)) ((bond patients) OR (burned patients)) risk among east ;*.