Perhaps you should try some spelling variations:
ban hanh » ban hang
lang van » dang van, tang van, hoang van
so dang » su dang, so dan, so dung
va danh » va dinh, va dan, va hanh
dang ky » dang y, dan ky, dong ky
hieu va » lieu va, hieu qua
lang xa » lang ha, dang xay
vi cua » vai cua, di cua
cua te » cua tu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: so dang ky ((lang xa) or (lang van)) hoi. hieu va cac du ((ban hanh) or (va danh)) vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so dang ky ((lang xa) OR (lang van)) hoi. hieu va cac du ((ban hanh) OR (va danh)) vi cua te.
• Adding a wildcard symbol may retrieve word variants: so dang ky ((lang xa) or (lang van)) hoi. hieu va cac du ((ban hanh) or (va danh)) vi cua te*.