Perhaps you should try some spelling variations:
cau treo » cau theo, cau tren, cau triet
van hanh » van thanh, ban hanh, van anh
vien cac » vien bach, vien dai, vien da
luc van » luoc van, luu van, duc van
cuu tre » cua tre, cau tren
te sach » toc sach
ve cac » va cac
y nang » ky nang, ly nang, v nang
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: te sach y nang x hoi. hieu ((ve cac) OR (vien cac)) luc van hanh kem ((cuu tre) or (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang x hoi. hieu ((ve cac) OR (vien cac)) luc van hanh kem ((cuu tre) OR (cau treo)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y nang x hoi. hieu ((ve cac) OR (vien cac)) luc van hanh kem ((cuu tre) or (cau treo))".
• Adding a wildcard symbol may retrieve word variants: te sach y nang x hoi. hieu ((ve cac) OR (vien cac)) luc van hanh kem ((cuu tre) or (cau treo))*.