Perhaps you should try some spelling variations:
present challenges » current challenges, assessment challenges
challenges tan » challenges call, challenges time, challenges 1
2 present » _ present, 3 present
wana yang » wang yang, wang yan, apa yang
tan zhong » tan hong, tan kong, can hong
zhong tai » hong tan, hong hai, zhong zhi
yana yi » yang yi
na y » na _, na 2, a y

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((wana yang) or (yana yi))na y 2 present challenges tan zhong tai ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((wana yang) OR (yana yi))na y 2 present challenges tan zhong tai ;.
• Adding a wildcard symbol may retrieve word variants: ((wana yang) or (yana yi))na y 2 present challenges tan zhong tai ;*.