Perhaps you should try some spelling variations:
sanh ky » hanh ky, sang ky, nganh ky
cua tre » cuu tre, cua triet, dua tren
va hanh » van hanh, va thanh, va danh
hieu ve » hieu va, hieu van
so sanh » do sanh
lang xa » dang xay, lang van
lang ha » long ha
ve cac » va cac, vien cac
cua te » cua tu
du va » dau va, tu va, su va

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 sanh ky ((lang xa) OR (lang ha)) hoi. hieu ve cac du va hanh vi ((cua tre) OR (cua te))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sanh ky ((lang xa) or (lang ha)) hoi. hieu ve cac du va hanh vi ((cua tre) OR (cua te))~".
• Adding a wildcard symbol may retrieve word variants: so sanh ky ((lang xa) or (lang ha)) hoi. hieu ve cac du va hanh vi ((cua tre) OR (cua te))*.