Perhaps you should try some spelling variations:
cost during » boost during, crust during, west during
during risk » using risk, during crises, during crisis
chen zhang » cheng zhang, zhen zhang, chen shuang
chen zheng » chen zhen, chen aizheng, cheng zhang
making eu » making _, making a, making 3
how shih » how six, how she

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: ((chen zhang) OR (chen zheng)) ((making eu) OR (ming lu)) cost during risk how shih ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((chen zhang) OR (chen zheng)) ((making eu) or (ming lu)) cost during risk how shih ;~".
• Adding a wildcard symbol may retrieve word variants: ((chen zhang) OR (chen zheng)) ((making eu) or (ming lu)) cost during risk how shih ;*.