Dung la cai dan o vietnam ngu qua...o tren cao vay..thang an trom nao giam leo vo? dong thoi rao mot cai khung nhu vay..khi xay ra hoa hoan,,,chi khac nao dua minh vao duong chet...cua so de thoang mat va khi chay thi xe thang cuu hoa co the tiep can nhung dem bit lai khong co mot loi ra...bo tay...day cung la kien thuc qua thap hoac la thong tin cung nhu hieu biet cua nguoi dan con o tinh trang kem..co the la do che do khong mo rong hieu biet cho nguoi dan...