public DataTable search(string name) { string str = "select a.masach, a.tensach, ls.maloaisach, a.soluong, a.make from sach as a, loaisach as ls where ls.tenloaisach = N'" + name + "' and ls.maloaisach = a.maloaisach"; DBMain dB = new DBMain(); DataTable table = dB.ExecuteQuery(str); return(table); }