Perhaps you should try some spelling variations:
ban hanh » ban hang
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va, hieu van
cac duc » cac du, cao duc, cac dac
cua tre » cuu tre, cua triet, dua tren
su sai » su tai, su hai, su dai
sai ky » sac ky
ve cac » va cac, vien cac
cua te » cua tu

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 sai ky lang xa hoi. hieu ve cac duc ((van ban) OR (ban hanh)) thai ((cua tre) OR (cua te))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sai ky lang xa hoi. hieu ve cac duc ((van ban) or (ban hanh)) thai ((cua tre) OR (cua te))~".
• Adding a wildcard symbol may retrieve word variants: su sai ky lang xa hoi. hieu ve cac duc ((van ban) or (ban hanh)) thai ((cua tre) OR (cua te))*.