Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
mai khoi » tai khoa, cac khoi, dai khoa
van hanh » van thanh, ban hanh, van anh
mai khoa » tai khoa, may khoa, dai khoa
hanh ki » hanh vi, hanh ky, hanh kien
xuc van » duc van, luc van, vuc van
tu sach » thu sach, su sach, te sach
vu nang » vuc nang, va nang, vu dang
sach vu » sach va, sach tu, sach uu
hieu va » hieu qua
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 sach vu nang ((mai khoi) or (mai khoa)). ((hieu va) OR (lieu va)) cam xuc van hanh ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach vu nang ((mai khoi) OR (mai khoa)). ((hieu va) OR (lieu va)) cam xuc van hanh ki su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach vu nang ((mai khoi) or (mai khoa)). ((hieu va) OR (lieu va)) cam xuc van hanh ki su triet".
• Adding a wildcard symbol may retrieve word variants: tu sach vu nang ((mai khoi) or (mai khoa)). ((hieu va) OR (lieu va)) cam xuc van hanh ki su triet*.