Perhaps you should try some spelling variations:
credit trading » credit training, credit rating, credit standing
trading value » trading volume, trading volumes, creating value
dual credit » rural credit, deals credit, equal credit
value cong » value co, value closing, value change
wang yong » wang yang, wang hyoung, wang yan
done sin » dong sin, done using, done so
a dual » _ dual

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((done sin) OR (wang yong)) a dual credit trading value cong shu ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((done sin) OR (wang yong)) a dual credit trading value cong shu ;*".