Perhaps you should try some spelling variations:
cost during » boost during, crust during, west during
during risk » using risk, during crises, during crisis
using eu » using e, using ed, using es
how safe » how safety, how space, how scale
ying eu » ying zhu, ying hua
how she » how some, how shih
zhen » zheng, when, chen

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

• Performing a fuzzy search may retrieve terms with similar spellings: zhen zhang ((ying eu) OR (using eu)) cost during risk ((how she) or (how safe)) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: zhen zhang ((ying eu) OR (using eu)) cost during risk ((how she) OR (how safe)) ;*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "zhen zhang ((ying eu) OR (using eu)) cost during risk ((how she) or (how safe)) ;*".