Perhaps you should try some spelling variations:
hanh hoi » hanh thoi, hanh noi, hanh hoa
ban hanh » ban hang
hieu van » hieu va, thien van, lieu va
cuu tre » cau tren, cau treo
cam duc » cam xuc, cao duc, pham duc
cua tre » cua te, cua triet, dua tren
duc ban » duc tan, duc van, dua ban
van cam » van nam, van lam, van cau
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang
su xac » pu xac, su cac
su sac » su sach, su cac

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: ((su sac) OR (su xac)) ky tang xa hoi. hieu van cam duc ban hanh hoi ((cua tre) OR (cuu tre))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sac) or (su xac)) ky tang xa hoi. hieu van cam duc ban hanh hoi ((cua tre) OR (cuu tre))~".
• Adding a wildcard symbol may retrieve word variants: ((su sac) or (su xac)) ky tang xa hoi. hieu van cam duc ban hanh hoi ((cua tre) OR (cuu tre))*.