Perhaps you should try some spelling variations:
dua tren » dung tren
te sach » toc sach
sach ky » sac ky, sach y, sach ty
ky tang » ky nang, ky dang, kho tang
tang ma » mang may, tang van
hieu ve » hieu va, hieu van
cao duc » dao duc, cao suc, giao duc
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau tren, cau treo
ma hoi » mai hoi, xa hoi, ma hoa
ve cao » va cao, ve bao, ve cac

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 ky tang ma hoi. hieu ve cao duc va hanh vi ((dua tren) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky tang ma hoi. hieu ve cao duc va hanh vi ((dua tren) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: te sach ky tang ma hoi. hieu ve cao duc va hanh vi ((dua tren) or (cuu tre))*.