question: ham kiem tra xau rong hay khong concode_field_sep PlaceHolder placeHolder concode_field_sep String unAccent concode_elem_sep String convertUTF8 concode_elem_sep String gioiTinh concode_elem_sep boolean notVaildNumber concode_elem_sep String getVaildString
target: boolean function ( String arg0 ) { if ( arg0 == null || arg0 . length ( ) == 0 ) return true ; return false ; }