Perhaps you should try some spelling variations:
training risk » trading risk, training crisis, defining risk
training cost » training costs, training course, training courses
dual credit » rural credit, deals credit, equal credit
yang y.c » yang yi, yang yao, yang 4.3
yang y » yang yi, yang _, yang 8
cong » congo, long, hong

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 ((yang y) OR (yang y.c)) dual credit ((training risk) OR (training cost)) cong shu ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "dong ((yang y) OR (yang y.c)) dual credit ((training risk) or (training cost)) cong shu ;~".
• Adding a wildcard symbol may retrieve word variants: dong ((yang y) OR (yang y.c)) dual credit ((training risk) or (training cost)) cong shu ;*.