Perhaps you should try some spelling variations:
zhang yunling » wang yanling, zhang chunlin, zhang yuqin
equal credit » equity credit, rural credit, total credit
trading cost » trading costs, training cost, trading case
dual credit » rural credit, deals credit, du credit
cost coping » post coping, port coping, cost computing
coping shu » cong shu
yala » ayala, yale, ala

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: zhang yunling yala ((dual credit) OR (equal credit)) trading cost coping shu ;~.
• Adding a wildcard symbol may retrieve word variants: zhang yunling yala ((dual credit) or (equal credit)) trading cost coping shu ;*.