Perhaps you should try some spelling variations:
ve triet » va trien
su triet » su viet, su tien
van hanh » van thanh, ban hanh, van anh
hanh ki » hanh vi, hanh ky, hanh kien
xuc van » duc van, luc van, vuc van
tu sach » thu sach, su sach, te sach
sach vu » sach va, sach tu, sach uu
tang ma » mang may, tang van
vu tang » vu dang, vu bang, vu nang
ma hoi » mai hoi, xa hoi, ma hoa
va cao » va co, va dao, va bao

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach vu tang ma hoi. hieu ((va cac) or (va cao)) xuc van hanh ki ((su triet) OR (ve triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach vu tang ma hoi. hieu ((va cac) OR (va cao)) xuc van hanh ki ((su triet) OR (ve triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach vu tang ma hoi. hieu ((va cac) or (va cao)) xuc van hanh ki ((su triet) OR (ve triet))".
• Adding a wildcard symbol may retrieve word variants: tu sach vu tang ma hoi. hieu ((va cac) or (va cao)) xuc van hanh ki ((su triet) OR (ve triet))*.