Perhaps you should try some spelling variations:
va thieu » va thiet, va hieu, va tieu
xuc ban » duc ban, cuc ban, quoc ban
xuc van » duc van, luc van, vuc van
ve cham » va cham, ve chat, vu cham
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
tang ma » mang may, tang van
nang ma » sang ma, nang cao, mang may
hieu ve » hieu va, hieu van
vi va » vi van, vai va, vu 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) or (tang ma)) hoi. hieu ve cham ((xuc van) or (xuc ban)) hanh vi va thieu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang ma) OR (tang ma)) hoi. hieu ve cham ((xuc van) OR (xuc ban)) hanh vi va thieu.
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang ma) or (tang ma)) hoi. hieu ve cham ((xuc van) or (xuc ban)) hanh vi va thieu*.