Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thanh vai » thanh hai, thanh van, thanh tai
ban thanh » ban hanh, ban hang
hieu van » thien van, lieu va, hieu ve
bay dua » cay dua, chay dua
dua ban » dia ban, cua ban, qua ban
su tien » su kien, su hien, tu tieng
hieu va » lieu va, hieu qua
mai hoi » mai khoi, dai hoi, lai hoi
y nang » ky nang, ly nang, v nang
vai su » va su, van su, lai su

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 y nang ((mai hoi) OR (ma hoa)). ((hieu van) OR (hieu va)) bay dua ban thanh vai su tien~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach y nang ((mai hoi) or (ma hoa)). ((hieu van) OR (hieu va)) bay dua ban thanh vai su tien~".
• Adding a wildcard symbol may retrieve word variants: thuoc sach y nang ((mai hoi) or (ma hoa)). ((hieu van) OR (hieu va)) bay dua ban thanh vai su tien*.