Perhaps you should try some spelling variations:
during risk » using risk, during crises, during crisis
liang ying » liang liying, huang ying, zhang ying
among heis » among ers, among hiv, among jews
yang yang » wang yang, wang yan
run cost » iran cost, can cost, run cash
eu cost » au costa, der cost, end cost

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: wang ((liang ying) or (yang yang)) ((run cost) or (eu cost)) during risk among heis ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: wang ((liang ying) OR (yang yang)) ((run cost) OR (eu cost)) during risk among heis ;.
• Adding a wildcard symbol may retrieve word variants: wang ((liang ying) or (yang yang)) ((run cost) or (eu cost)) during risk among heis ;*.