Perhaps you should try some spelling variations:
ratings risk » patients risk
cost ratings » cost savings, costs savings, bond ratings
huang ying » huang jing, huang ting, huang yang
liang ying » liang liying, zhang ying, jiang yajing
among men » among women
die cost » diet cost, die post, die ost

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 ((((wang yan) OR (liang ying))) OR (huang ying)) die cost ratings risk among men ;~.
• Adding a wildcard symbol may retrieve word variants: wang ((((wang yan) or (liang ying))) or (huang ying)) die cost ratings risk among men ;*.