Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
dung sai » dung tai, dung va, dung dat
danh sai » danh bat, danh dau, hanh san
su sach » so sach, vu sach
thuc xa » thuc xay, tuc xa, thuc va
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
hieu he » hiem he, hieu le, hieu hien
nang ma » tang ma, sang ma, nang 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 nang ma hoi. ((hieu he) OR (hieu ve)) nam thuc xa ((danh sai) or (dung sai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ma hoi. ((hieu he) OR (hieu ve)) nam thuc xa ((danh sai) OR (dung sai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang ma hoi. ((hieu he) OR (hieu ve)) nam thuc xa ((danh sai) or (dung sai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ma hoi. ((hieu he) OR (hieu ve)) nam thuc xa ((danh sai) or (dung sai)) cua tre*.