Perhaps you should try some spelling variations:
retaining values » retaining valued, rethinking values, refining values
credit retaining » credit rationing, credit training, credit rating
dual credit » rural credit, deals credit, equal credit
values cong » values coding, values among, values co
yang yang » wang yang, wang yan
a dual » _ dual

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: (((dong OR doing) sin) OR (yang yang)) a dual credit retaining values cong shu ;~.
• Adding a wildcard symbol may retrieve word variants: (((dong or doing) sin) or (yang yang)) a dual credit retaining values cong shu ;*.