Perhaps you should try some spelling variations:
tang van » dang van, hoang van, trong van
thu sach » tu sach, thuat sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
ve triet » va trien, su triet
hieu va » lieu va, hieu qua
lam luu » tam luu
luu van » cuu van, luan van, luu hanh
hanh de » hanh ve, hanh kem
va lam » van lam, va lap

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach y ((mang may) or (((tang ma) OR (tang van)))) hoi. hieu va lam luu van hanh de ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y ((mang may) OR (((tang ma) OR (tang van)))) hoi. hieu va lam luu van hanh de ve triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y ((mang may) or (((tang ma) OR (tang van)))) hoi. hieu va lam luu van hanh de ve triet".
• Adding a wildcard symbol may retrieve word variants: thu sach y ((mang may) or (((tang ma) OR (tang van)))) hoi. hieu va lam luu van hanh de ve triet*.