Perhaps you should try some spelling variations:
van sach » ban sach, van hach, ngan sach
hanh tai » thanh tai, hang tai, han tai
cau treo » cau theo, cau tren, cau triet
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
va sach » va cach, a sach, vu sach
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky nang x hoi. hieu ((va sach) or (van sach)) nuoc va hanh tai ((cua tre) or (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang x hoi. hieu ((va sach) OR (van sach)) nuoc va hanh tai ((cua tre) OR (cau treo)).
• Adding a wildcard symbol may retrieve word variants: su sach ky nang x hoi. hieu ((va sach) or (van sach)) nuoc va hanh tai ((cua tre) or (cau treo))*.