Perhaps you should try some spelling variations:
vu sach » vu bach, su sach, vu khach
dinh du » dinh duc, dinh cu, dinh tu
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
cuu tre » cua tre, cau tren, cau treo
ky tang » ky nang, ky dang, kho tang
ma hoi » mai hoi, ma hoa, me hoi
xuc va » duc va, tuc va, xac va
luc va » duc va, tuc va, loc va
du cuu » tu cuu
va cam » va cham, va cac, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ky tang ((ma hoi) OR (xa hoi)). hieu va cam ((xuc va) or (luc va)) dinh du cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky tang ((ma hoi) OR (xa hoi)). hieu va cam ((xuc va) OR (luc va)) dinh du cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky tang ((ma hoi) OR (xa hoi)). hieu va cam ((xuc va) or (luc va)) dinh du cuu tre".
• Adding a wildcard symbol may retrieve word variants: vu sach ky tang ((ma hoi) OR (xa hoi)). hieu va cam ((xuc va) or (luc va)) dinh du cuu tre*.