Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh dat » thanh san, thanh hai, thanh van
dua tren » dung tren
hoc sach » hoc sinh, hoc cac, hoc anh
cua viet » ca viet, hoa viet, cua vat
hieu ve » hieu va, hieu van
cac duc » cac du, cao duc, cac dac
duc ban » duc tan, duc van, dua ban
cua tre » cua te, cuu tre, cua triet
nang ma » tang ma, sang ma, nang cao
ve cac » va cac, vien cac
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa

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: hoc sach y nang ma hoi. hieu ve cac duc ban thanh dat ((((cua tre) OR (dua tren))) OR (cua viet))~.
• Adding a wildcard symbol may retrieve word variants: hoc sach y nang ma hoi. hieu ve cac duc ban thanh dat ((((cua tre) or (dua tren))) or (cua viet))*.