Perhaps you should try some spelling variations:
4 challenges » 3 challenges, 2 challenges
wan chan » han chang, wang chau, mun chan
chan jan » chain jane, chan alan, chan kang
dan yang » daun yang, tan yang, wang yang
yi chang » ii chang, ying chang, jin chang
yi dang » yi gang, yi yang
m dan » am dan, me dan, _ dan

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

• Performing a fuzzy search may retrieve terms with similar spellings: wan chan jan m dan yang ((((yi dang) OR (yi chang))) or (4 challenges)) (hai or hadi) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: wan chan jan m dan yang ((((yi dang) OR (yi chang))) OR (4 challenges)) (hai OR hadi) ;*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wan chan jan m dan yang ((((yi dang) OR (yi chang))) or (4 challenges)) (hai or hadi) ;*".