Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
duc van » duc va, duc tan, duc manh
dua ban » dia ban, cua ban, qua ban
hieu va » lieu va, hieu qua
tang ma » mang may, tang van
ky tang » ky nang, ky dang, kho tang
cuu tre » cua tre, cau tren, cau treo
va cam » va cham, va cac, va cao
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: su sach ky tang ma hoi. hieu va cam ((dua ban) or (duc van)) hanh vi ((su triet) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky tang ma hoi. hieu va cam ((dua ban) OR (duc van)) hanh vi ((su triet) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: su sach ky tang ma hoi. hieu va cam ((dua ban) or (duc van)) hanh vi ((su triet) or (cuu tre))*.