Perhaps you should try some spelling variations:
cost ratings » cost savings, costs savings, bond ratings
ratings risk » patients risk
wang yong » wang yang, wang hyoung, wang yan
woman can » women can, man can, woman c
dang hari » dang hai
tong hui » wang hui
yan can » yan clan, man can, yan cong

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 yong ((yan can) OR (woman can)) cost ratings risk ((tong hui) OR (dang hari)) ;~.
• Adding a wildcard symbol may retrieve word variants: wang yong ((yan can) or (woman can)) cost ratings risk ((tong hui) or (dang hari)) ;*.