Perhaps you should try some spelling variations:
crises china » crisis china's, classes china, crises asia
wang yidan » wang yan
can postal » bank postal, a postal, can costa
china text » china teil, china term, china context
der cost » oder cost, user cost, debt cost
eu cost » au costa, end cost, eu court

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: wang yidan ying ((((eu cost) OR (can postal))) OR (der cost)) during crises china text ;~.
• Adding a wildcard symbol may retrieve word variants: wang yidan ying ((((eu cost) or (can postal))) or (der cost)) during crises china text ;*.