Perhaps you should try some spelling variations:
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
hieu va » lieu va, hieu qua
truc va » thuc va, thuc vat, trung va
va tinh » may tinh
tinh va » tich va, trinh van, trinh vat
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
va cau » van cau, va cac, va dau

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky tang xa hoi. hieu va cau truc va tinh va ((((cua tre) OR (cuu tre))) OR (cua vat))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky tang xa hoi. hieu va cau truc va tinh va ((((cua tre) OR (cuu tre))) or (cua vat))~".
• Adding a wildcard symbol may retrieve word variants: su sach ky tang xa hoi. hieu va cau truc va tinh va ((((cua tre) OR (cuu tre))) or (cua vat))*.