Perhaps you should try some spelling variations:
tested using » tests using, testing using, system using
test using » tests using, testing using
kong saur » kong sar, kong siu, kong your
yang api » yang dali, yang di, yang xi
yang jui » yang judy, yang di, yang xi
nan kong » tan kong
wan yan » wang yan, nan yan, wai yan

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: wan yan ((yang api) OR (yang jui)) ((tested using) OR (test using)) nan kong saur ;~.
• Adding a wildcard symbol may retrieve word variants: wan yan ((yang api) or (yang jui)) ((tested using) or (test using)) nan kong saur ;*.