Perhaps you should try some spelling variations:
dung sai » dung tai, dung va, dung dat
danh sai » danh bat, danh dau, hanh san
nam thuc » nam thuoc, am thuc, nam thu
su sach » so sach
thuc xa » thuc xay, tuc xa, thuc va
cua tre » cua te, cuu tre, cua triet
hieu he » hieu ve, hiem he, hieu le
tang ma » mang may, tang van
ky tang » ky nang, ky dang, kho tang
vu sach » vu bach, vu khach
ma hoi » mai hoi, xa hoi, ma hoa
he nam » ha nam, nghe nam

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) OR (vu sach)) ky tang ma hoi. hieu he 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) OR (vu sach)) ky tang ma hoi. hieu he 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) OR (vu sach)) ky tang ma hoi. hieu he nam thuc xa ((danh sai) or (dung sai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: ((su sach) OR (vu sach)) ky tang ma hoi. hieu he nam thuc xa ((danh sai) or (dung sai)) cua tre*.