Perhaps you should try some spelling variations:
training comet » training women, training cost, training comments
trading case » trading costs, trade case
dual credit » rural credit, deals credit, equal credit
a credit » bad credit
dong » doing, long, done
sin » sign, sind, skin
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: dong sin ya ((a credit) or (dual credit)) ((trading case) or (training comet)) cong shu ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: dong sin ya ((a credit) OR (dual credit)) ((trading case) OR (training comet)) cong shu ;.
• Adding a wildcard symbol may retrieve word variants: dong sin ya ((a credit) or (dual credit)) ((trading case) or (training comet)) cong shu ;*.