Perhaps you should try some spelling variations:
credit training » credit rationing, credit rating, credit granting
credit trading » credit rating, credit standing, credit creating
yang yang » wang yang, wang yan
case wong » case work
wong shiu » wong siu, cong shu, song shin
yang yao » wang yan, yang yi, yang fan

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 ((yang yao) OR (yang yang)) du ((credit trading) OR (credit training)) case wong shiu ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang ((yang yao) OR (yang yang)) du ((credit trading) or (credit training)) case wong shiu ;~".
• Adding a wildcard symbol may retrieve word variants: wang ((yang yao) OR (yang yang)) du ((credit trading) or (credit training)) case wong shiu ;*.