Perhaps you should try some spelling variations:
doanh than » doanh thanh, doanh nhan, doanh phan
su triet » su tien, ve triet
hieu van » hieu va, thien van, lieu va
van chat » cao chat
tu sach » thu sach, su sach, te sach
su viet » so viet
sach ky » sac ky, sach y, sach ty
ma khoi » mai khoi, ra khoi, xa khoi
nang ma » tang ma, sang ma, nang cao
xac va » tac va, ac va, bac va

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 nang ma khoi. hieu van chat ((xac va) or (duc va)) doanh than ((su triet) OR (su viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ma khoi. hieu van chat ((xac va) OR (duc va)) doanh than ((su triet) OR (su viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang ma khoi. hieu van chat ((xac va) or (duc va)) doanh than ((su triet) OR (su viet))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ma khoi. hieu van chat ((xac va) or (duc va)) doanh than ((su triet) OR (su viet))*.