Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
ky sang » ky nang, ky dang, ky tang
sang ma » tang ma, nang ma, sang tao
hieu ve » hieu van
danh vi » dinh vi, danh di, danh va
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
xuc va » duc va, tuc va, luc va
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: tu sach ky sang ma hoi. ((hieu ve) or (hieu va)) cam xuc va ((danh vi) OR (hanh vi)) cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky sang ma hoi. ((hieu ve) OR (hieu va)) cam xuc va ((danh vi) OR (hanh vi)) cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky sang ma hoi. ((hieu ve) or (hieu va)) cam xuc va ((danh vi) OR (hanh vi)) cua vat".
• Adding a wildcard symbol may retrieve word variants: tu sach ky sang ma hoi. ((hieu ve) or (hieu va)) cam xuc va ((danh vi) OR (hanh vi)) cua vat*.