Perhaps you should try some spelling variations:
van trang » vang trang, van thang, va trang
hieu quan » lieu quan, thien quan, lien quan
su triet » su viet, su tien, ve triet
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
trang ma » trang mat, trang mau, trang va
bac van » bach van, cac van, ban van
cam luc » cam xuc, cau luc
ma hoi » mai hoi, xa hoi, ma hoa
tu bac » tu ban, tu cac, tu bat
ki su » ky su

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu bac van trang ma hoi. ((hieu qua) or (hieu quan)) cam luc ((van hanh) or (ban hanh)) ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu bac van trang ma hoi. ((hieu qua) OR (hieu quan)) cam luc ((van hanh) OR (ban hanh)) ki su triet.
• Adding a wildcard symbol may retrieve word variants: tu bac van trang ma hoi. ((hieu qua) or (hieu quan)) cam luc ((van hanh) or (ban hanh)) ki su triet*.