Perhaps you should try some spelling variations:
crises china » crisis china's, classes china, crises asia
china stein » china shen, china step, china teil
wang yuhan » wang luhang, wang yan, wang yidan
can costa » can cost, can postal, da costa
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 yuhan ying ((((eu cost) OR (can costa))) OR (der cost)) during crises china stein ;~.
• Adding a wildcard symbol may retrieve word variants: wang yuhan ying ((((eu cost) or (can costa))) or (der cost)) during crises china stein ;*.