How can i add more than one List in a unique List and show it in a ListView - Xamrin Forms

I want to put more than one List into a unique List, but i have a problem, to make a List you need to put a Model and one of each List that i have had his unique Model

        public Task<List<SQLite_ventas_factura>> GetVentasFacturaAsync()
        {
            return _database.Table<SQLite_ventas_factura>().ToListAsync();
        }

        public Task<List<SQLite_ventas_pedido>> GetVentasPedidoAsync()
        {
            return _database.Table<SQLite_ventas_pedido>().ToListAsync();
        }

I have 2 List with differents Model, my question here is. How can i put this List in one unique List to show it in a ListView