Perhaps you should try some spelling variations:
ying yang » yang yang, ying chang, wang yang
main line » main die, thin line
yin yang » yi yang, yin fang, yin hang
api test » ai test, ii test
law main » law pain, law making, new main
i test » ai test, i testi, ii test
yeon » leon, deon, yen

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: wang ((ying yang) OR (yin yang)) ((api test) OR (i test)) law main line yeon ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang ((ying yang) or (yin yang)) ((api test) OR (i test)) law main line yeon ;~".
• Adding a wildcard symbol may retrieve word variants: wang ((ying yang) or (yin yang)) ((api test) OR (i test)) law main line yeon ;*.