Perhaps you should try some spelling variations:
thanh trung » thanh tung
doanh quang » doan quang, doanh quan, doanh luan
hieu lang » chieu sang, hieu quang, nhieu tang
trung hoc » trung quoc
cong cong » trong cong, dung cong, dang cong
quang cao » nang cao, quang nam
hoc hieu » hoc thieu, hoc hien, doc hieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hieu lang - thanh trung hoc ((cong cong) or (cong dong)) doanh quang cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu lang - thanh trung hoc ((cong cong) OR (cong dong)) doanh quang cao.
• Adding a wildcard symbol may retrieve word variants: hoc hieu lang - thanh trung hoc ((cong cong) or (cong dong)) doanh quang cao*.