Perhaps you should try some spelling variations:
nganh duoc » nganh suc
hieu quan » lieu quan, thien quan, lien quan
ky nganh » ky nang, ly ngan, k ngan
duoc hoi » quoc hoi, duoc hoc, duoc si
ve triet » va trien, su triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
lam tuc » lam thuoc, lam truoc, luat tuc
xa hanh » xa thanh, xa khanh, va hanh
vi ve » va ve, gi ve, ve ve

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 ky nganh duoc hoi. ((hieu quan) or (hieu qua)) lam tuc xa hanh vi ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nganh duoc hoi. ((hieu quan) OR (hieu qua)) lam tuc xa hanh vi ve triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nganh duoc hoi. ((hieu quan) or (hieu qua)) lam tuc xa hanh vi ve triet*.