Perhaps you should try some spelling variations:
ky tang » ky nang, ky dang, kho tang
tang ma » mang may, tang van
hieu ve » hieu van
hieu va » lieu va, hieu qua
cam tuc » cam xuc, cam tu, nam thuc
so sac » so sach, so dac
sac ky » cac ky, sai ky
ma hoi » mai hoi, xa hoi, ma hoa
xa dan » ca dan, xa dai, va dan
dan vi » doan vi, don vi, dan va
vi hoc » li hoc, va hoc
hien » bien, vien, tien

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sac ky tang ma hoi. ((hieu ve) or (hieu va)) cam tuc xa dan vi hoc hien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sac ky tang ma hoi. ((hieu ve) OR (hieu va)) cam tuc xa dan vi hoc hien.
• Adding a wildcard symbol may retrieve word variants: so sac ky tang ma hoi. ((hieu ve) or (hieu va)) cam tuc xa dan vi hoc hien*.