Perhaps you should try some spelling variations:
cau treo » cau theo, cau tren, cau triet
nang xay » dang xay, nganh xay, nang xuan
hanh dai » hanh tai, hanh dao, vanh dai
cua tre » cua te, cuu tre, cua triet
va hanh » van hanh, va thanh, va danh
truc va » thuc va, thuc vat, trung va
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
xay hoi » xa hoi, tay hoi, cay phoi
va cam » va cham, va cao, va cai

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 xay hoi. hieu ((va cam) or (va cac)) truc va hanh dai ((cua tre) or (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xay hoi. hieu ((va cam) OR (va cac)) truc va hanh dai ((cua tre) OR (cau treo)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xay hoi. hieu ((va cam) or (va cac)) truc va hanh dai ((cua tre) or (cau treo))*.