Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
nam thuc » nam thuoc, nam thu, nam tu
lang ha » long ha
ky lang » ky nang, ky dang, ky tang
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
vai cuu » vai cua
cuu tre » cua tre, cau tren, cau treo
ha hoi » hoa hoi, ha noi, xa hoi

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ky lang ha hoi. hieu va ((nam thuc) OR (am thuc)) ((va dao) OR (ca dao)) vai cuu tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ky lang ha hoi. hieu va ((nam thuc) OR (am thuc)) ((va dao) or (ca dao)) vai cuu tre~".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ky lang ha hoi. hieu va ((nam thuc) OR (am thuc)) ((va dao) or (ca dao)) vai cuu tre*.