Perhaps you should try some spelling variations:
patients risk » patient risk, patients links, patients si
wei yang's » yiwei wang's
risk along » risk among, ask along
along who » along two, wrong who
wei yang » pei yang, wei wang, wei shang
hua cost » a cost, eu cost, run cost
au costa » can costa, _ costa, da costa

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

• Performing a fuzzy search may retrieve terms with similar spellings: wang ((wei yang) OR (wei yang's)) ((hua cost) or (au costa)) patients risk along who ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: wang ((wei yang) OR (wei yang's)) ((hua cost) OR (au costa)) patients risk along who ;*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang ((wei yang) OR (wei yang's)) ((hua cost) or (au costa)) patients risk along who ;*".