Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
truc van » truc va, thuc van, truc ban
so sach » so sanh, co sach, hoc sach
cua tre » cuu tre, cua triet, dua tren
hanh de » hanh ve, hanh kem
hieu ve » hieu va, hieu van
bo sach » co sach, hoc sach
ve cau » ke cau, va cau, ve cac
va ban » van ban, va bai, va bao
cua te » cua tu
x hoi » xa hoi, o hoi, x ho
ban x » ban xu, ban _, ban 1

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: ((so sach) OR (bo sach)) va ban x hoi. hieu ve cau truc van hanh de ((cua tre) OR (cua te))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) OR (bo sach)) va ban x hoi. hieu ve cau truc van hanh de ((cua tre) or (cua te))~".
• Adding a wildcard symbol may retrieve word variants: ((so sach) OR (bo sach)) va ban x hoi. hieu ve cau truc van hanh de ((cua tre) or (cua te))*.