Perhaps you should try some spelling variations:
training risk » trading risk, training visit, training work
training cost » training costs, training course, trading costs
dual credit » rural credit, equal credit, rural credits
yang yang » wang yang, wang yan
wang yong » wang yang, wang hyoung, wang yan
y dual » _ dual, a dual
cong » congo, long, hong

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((yang yang) OR (wang yong)) y dual credit ((training risk) or (training cost)) cong shu ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((yang yang) OR (wang yong)) y dual credit ((training risk) OR (training cost)) cong shu ;.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((yang yang) OR (wang yong)) y dual credit ((training risk) or (training cost)) cong shu ;".
• Adding a wildcard symbol may retrieve word variants: ((yang yang) OR (wang yong)) y dual credit ((training risk) or (training cost)) cong shu ;*.