Perhaps you should try some spelling variations:
ratings risk » patients risk
cost ratings » cost savings, costs savings, bond ratings
liang yang » wang yang, yang yang, huang yang
liang ying » liang liying, huang ying, zhang ying
jie cost » die cost, time cost, diet cost
among eu » among men, among _, among 15

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "wang ((liang yang) OR (liang ying)) jie cost ratings risk among eu ;~".
• Adding a wildcard symbol may retrieve word variants: wang ((liang yang) OR (liang ying)) jie cost ratings risk among eu ;*.