Perhaps you should try some spelling variations:
jeong dahyeon » jeong hyeok
seung yeon » jeong yeon, seung joon, seung won
jeang yean » jeong yeon
wang wang » wang liang, wang yan, wang yong
wang yang » wang yan, wang liang, wang yanling
yang ai » yang di, yang xi, yang yi
ai test » api test, i test, ii test
test a » test _, test 4, test 5
a min » a main, a mini, a mine

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 wang yang ai test a min ((seung yeon) OR (((jeong dahyeon) OR (jeang yean)))) ;~.
• Adding a wildcard symbol may retrieve word variants: wang wang yang ai test a min ((seung yeon) or (((jeong dahyeon) or (jeang yean)))) ;*.