Perhaps you should try some spelling variations:
hoc vien » hoc hien, hoc viet, hoc tieng
mai hoi » mai khoi, dai hoi, lai hoi
hieu va » lieu va, hieu qua
hieu ve » hieu van
ky tang » ky nang, ky dang, kho tang
ma hoi » xa hoi, ma hoa, me hoi
sac ky » cac ky, sai ky
xuc va » duc va, tuc va, luc va
va dan » ca dan, va dao, va dau
dan vi » doan vi, don vi, dan va
vi hoc » li hoc, va hoc
so sac » so sach, so dac

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) or (mai hoi)). ((hieu ve) or (hieu va)) cam xuc va dan vi hoc vien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sac ky tang ((ma hoi) OR (mai hoi)). ((hieu ve) OR (hieu va)) cam xuc va dan vi hoc vien.
• Adding a wildcard symbol may retrieve word variants: so sac ky tang ((ma hoi) or (mai hoi)). ((hieu ve) or (hieu va)) cam xuc va dan vi hoc vien*.