Perhaps you should try some spelling variations:
sieu viet » dien viet, bien viet, viet viet
thanh dat » thanh san, thanh hai, thanh van
thu sach » tu sach, thuat sach, thuoc sach
xa thanh » va thanh, ha thanh, ta thanh
sach ky » sac ky, sach y, sach ty
su viet » so viet
hieu va » lieu va
dang ma » dang mau, dang mam, dang mat
ky dang » ky nang, ky danh
co tuc » co thuc, co tu, co toc
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: thu sach ky dang ma hoi. ((hieu va) or (hieu qua)) co tuc xa thanh dat ((sieu viet) or (su viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky dang ma hoi. ((hieu va) OR (hieu qua)) co tuc xa thanh dat ((sieu viet) OR (su viet)).
• Adding a wildcard symbol may retrieve word variants: thu sach ky dang ma hoi. ((hieu va) or (hieu qua)) co tuc xa thanh dat ((sieu viet) or (su viet))*.