Perhaps you should try some spelling variations:
thanh trung » thanh tung
trung tran » trung tuan, trung thanh, trung tam
tran trung » tran trong, tran tung, trac trung
trung cong » truong cong, trong cong, trung uong
hieu quan » hieu qua, lieu quan, thien quan
chu quang » chat quang, vu quang
cong san » cong tac
san toan » van toan, dan toan, manh toan
toan cao » toan ban, toan tap

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: ho ((hieu quan) OR (chu quang)) - thanh trung tran trung cong san toan cao~.
• Adding a wildcard symbol may retrieve word variants: ho ((hieu quan) or (chu quang)) - thanh trung tran trung cong san toan cao*.