Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
va triet » va thiet, va trien, ve triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
va hanh » va thanh, va danh, ban hanh
ma hoi » mai hoi, xa hoi, ma hoa
va am » va lam, va cam

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