Perhaps you should try some spelling variations:
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu van
hieu va » lieu va, hieu qua
cac xuc » cam xuc, cac nuoc, chat xuc
va hanh » van hanh, va thanh, va danh
ma hoi » mai hoi, xa hoi, ma hoa
vi cua » vai cua, di cua

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 nang ma hoi. ((hieu ve) OR (hieu va)) cac xuc ((va hanh) or (gia thanh)) vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ma hoi. ((hieu ve) OR (hieu va)) cac xuc ((va hanh) OR (gia thanh)) vi cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang ma hoi. ((hieu ve) OR (hieu va)) cac xuc ((va hanh) or (gia thanh)) vi cua vat".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ma hoi. ((hieu ve) OR (hieu va)) cac xuc ((va hanh) or (gia thanh)) vi cua vat*.