Sum up the away team goal scored by both Daan Smith and Filipe Ferreira.
Daan Smith refers to player_name = 'Daan Smith'; Filipe Ferreira refers to player_name = 'Filipe Ferreira'
SELECT SUM(t2.away_team_goal) FROM Player AS t1 INNER JOIN match AS t2 ON t1.player_api_id = t2.away_player_5 WHERE t1.player_name IN ('Daan Smith', 'Filipe Ferreira')