Perhaps you should try some spelling variations:
cau treo » cau theo, cau tren, cau triet
te sach » toc sach
hieu ve » hieu va, hieu van
cao duc » dao duc, cao suc, giao duc
va hanh » van hanh, va thanh, va danh
hanh di » hanh vi, hanh de, hang di
y nang » ky nang, ly nang, v nang
ve cao » va cao, ve bao, ve cac
x hoi » xa hoi, x ho, 5 hoi
o hoi » co hoi, o hoc, o hai
thiet » thieu

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) or (o hoi)). hieu ve cao duc va hanh di ((cau treo) or (va thiet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang ((x hoi) OR (o hoi)). hieu ve cao duc va hanh di ((cau treo) OR (va thiet)).
• Adding a wildcard symbol may retrieve word variants: te sach y nang ((x hoi) or (o hoi)). hieu ve cao duc va hanh di ((cau treo) or (va thiet))*.