Perhaps you should try some spelling variations:
cau treo » cau theo, cau tren, cau triet
vat xanh » vat thanh, sat anh, dat anh
cua tre » cua te, cuu tre, cua triet
xanh di » danh di, vanh dai, xanh tai
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
van bac » van ban, van bao, van hac
nang ma » tang ma, sang ma, nang cao
van hai » van ha, van chat, van hanh
ma hoi » mai hoi, xa hoi, ma hoa

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 ((van bac) or (van hai)) thuc vat xanh di ((cua tre) or (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ma hoi. hieu ((van bac) OR (van hai)) thuc vat xanh di ((cua tre) OR (cau treo)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ma hoi. hieu ((van bac) or (van hai)) thuc vat xanh di ((cua tre) or (cau treo))*.