Perhaps you should try some spelling variations:
changed john » changed our, changed post, changed rome
change john » chasse john, change japan, channon john
wang yao » wang yan, yang yao, gang yao
yao yang » yang yang
wong sau » wong sam, wong siu, wong shiu
a when » 4 when, 1 when, 2 when
3 when » 4 when

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

• Performing a fuzzy search may retrieve terms with similar spellings: wang yao yang ((a when) OR (3 when)) ((change john) or (changed john)) wong sau ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: wang yao yang ((a when) OR (3 when)) ((change john) OR (changed john)) wong sau ;.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang yao yang ((a when) OR (3 when)) ((change john) or (changed john)) wong sau ;".
• Adding a wildcard symbol may retrieve word variants: wang yao yang ((a when) OR (3 when)) ((change john) or (changed john)) wong sau ;*.