Perhaps you should try some spelling variations:
doanh ban » doanh bat, doanh van, doanh nhan
cua triet » su triet, va triet
hieu van » hieu va, thien van, lieu va
cua viet » ca viet, hoa viet, cua vat
te sach » toc sach
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
van lam » van nam
duoc va » nuoc va, duoc ma, duong va

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky lang xa hoi. hieu van lam ((duoc va) or (duc va)) doanh ban ((cua triet) OR (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky lang xa hoi. hieu van lam ((duoc va) OR (duc va)) doanh ban ((cua triet) OR (cua viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky lang xa hoi. hieu van lam ((duoc va) or (duc va)) doanh ban ((cua triet) OR (cua viet))".
• Adding a wildcard symbol may retrieve word variants: te sach ky lang xa hoi. hieu van lam ((duoc va) or (duc va)) doanh ban ((cua triet) OR (cua viet))*.