Perhaps you should try some spelling variations:
cao thuoc » cay thuoc, cua thuoc, nam thuoc
thu sach » tu sach, thuat sach, thuoc sach
dua tren » dung tren
thuoc va » thuc va, thuoc ma, thuong va
hieu va » lieu va, hieu qua
tang ma » mang may, tang van
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
ky tang » ky nang, ky dang, kho tang
cuu tre » cua tre, cau tren, cau treo
ma hoi » mai hoi, xa hoi, ma hoa
va cao » va cac, va co, va dao
cua tu » cua tuc, cua su, cua cu

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: thu sach ky tang ma hoi. hieu va cao thuoc va hanh vi ((((dua tren) OR (cua tu))) OR (cuu tre))~.
• Adding a wildcard symbol may retrieve word variants: thu sach ky tang ma hoi. hieu va cao thuoc va hanh vi ((((dua tren) or (cua tu))) or (cuu tre))*.