Perhaps you should try some spelling variations:
hieu luan » hieu luat, hieu quan, tieu luan
su triet » su viet, su tien, ve triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
mang xa » lang xa, mang may, dang xay
nang ma » tang ma, sang ma, nang cao
van duc » van duy, van du, tran duc
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi

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 ((mang xa) or (nang ma)) hoi. hieu luan van duc va hanh va su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((mang xa) OR (nang ma)) hoi. hieu luan van duc va hanh va su triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((mang xa) or (nang ma)) hoi. hieu luan van duc va hanh va su triet*.