gistfile1.cs

            var gatewaysByDestinationAndShipQuery = session.Query<Available_Gateway, Available_Gateways>();
            foreach (var destination in destinations)
            {
                gatewaysByDestinationAndShipQuery = gatewaysByDestinationAndShipQuery.Where(x => x.PortCodes.Any(y => destination == y));
            }

            foreach (var ship in ships)
            {
                gatewaysByDestinationAndShipQuery = gatewaysByDestinationAndShipQuery.Where(x => x.ShipCodes.Any(y => ship == y));
            }