Perhaps you should try some spelling variations:
ratings risk » patients risk
yan yang » yang yang, yao yang, dan yang
can cost » can costa, can lost, chain cost
can post » can lost, can past, can postal
how some » how women
wan yan » wang yan, nan yan, wai yan
eu cost » au costa, der cost, end cost
how shu » how she, how shih, how slum

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

• Performing a fuzzy search may retrieve terms with similar spellings: wan yan yang ((((eu cost) or (can cost))) or (can post)) ratings risk ((how shu) or (how some)) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: wan yan yang ((((eu cost) OR (can cost))) OR (can post)) ratings risk ((how shu) OR (how some)) ;.
• Adding a wildcard symbol may retrieve word variants: wan yan yang ((((eu cost) or (can cost))) or (can post)) ratings risk ((how shu) or (how some)) ;*.