Perhaps you should try some spelling variations:
hanh hai » thanh hai, nhanh hai, hang hai
cau tren » cu tren, dau tren, ca tren
te sach » toc sach
hieu va » lieu va, hieu qua
cao duc » dao duc, cao suc, giao duc
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau treo
y nang » ly nang, v nang, may nang
ma hoi » mai hoi, xa hoi, ma hoa
va cao » va cac, va co, va dao

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) or (ky nang)) ma hoi. hieu va cao duc va hanh hai ((cuu tre) OR (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((y nang) OR (ky nang)) ma hoi. hieu va cao duc va hanh hai ((cuu tre) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((y nang) or (ky nang)) ma hoi. hieu va cao duc va hanh hai ((cuu tre) OR (cau tren))".
• Adding a wildcard symbol may retrieve word variants: te sach ((y nang) or (ky nang)) ma hoi. hieu va cao duc va hanh hai ((cuu tre) OR (cau tren))*.