Perhaps you should try some spelling variations:
can thiet » dan thiet, cac thiet, cad thiet
thu sach » tu sach, thuat sach, thuoc sach
pham soc » cham soc, pham ngoc, pham sach
va thanh » gia thanh, ban thanh, va tinh
van hanh » van thanh, ban hanh, van anh
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
hieu su » hieu sau, tieu su, hieu so
su pham » san pham
ma hoi » mai hoi, xa hoi, ma hoa
vi can » voi can, vi van, i can

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 ky nang ma hoi. hieu su pham soc ((va thanh) or (van hanh)) vi can thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang ma hoi. hieu su pham soc ((va thanh) OR (van hanh)) vi can thiet.
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang ma hoi. hieu su pham soc ((va thanh) or (van hanh)) vi can thiet*.