Perhaps you should try some spelling variations:
viet dung » viet hung, viet huong, viet trung
vat dung » van dung, va dung, mat duong
ky dang » ky nang, ky danh
dang xa » dang xay, lang xa, dang ha
hieu ve » hieu va, hieu van
cua tre » cuu tre, cua triet, dua tren
so sac » so sach, so dac
sac ky » cac ky, sai ky
ve tam » ve tac, ve tai, va tam
tam tu » nam tu, cam tu, dam tu
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: so sac ky dang xa hoi. hieu ve tam tu ((vat dung) OR (viet dung)) cho ((cua tre) OR (cua te))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sac ky dang xa hoi. hieu ve tam tu ((vat dung) OR (viet dung)) cho ((cua tre) or (cua te))~".
• Adding a wildcard symbol may retrieve word variants: so sac ky dang xa hoi. hieu ve tam tu ((vat dung) OR (viet dung)) cho ((cua tre) or (cua te))*.