Perhaps you should try some spelling variations:
lang yanling » wang yanling, wang yangming, zhang yunling
equal credit » equity credit, rural credit, total credit
trading cost » trading costs, training cost, trading case
dual credit » rural credit, deals credit, du credit
yala » ayala, yale, ala
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: lang yanling yala ((dual credit) OR (equal credit)) trading cost cong shu ;~.
• Adding a wildcard symbol may retrieve word variants: lang yanling yala ((dual credit) or (equal credit)) trading cost cong shu ;*.