Manchester United ensured they will compete in the Champions League after beating their Dutch opponents 2-0.
Goals from Paul Pogba and Henrikh Mkhitaryan ensured Jose Mourinho's men are the most decorated English club in history.
But Bosz wasn't too impressed with the quality of the final in Stockholm, labelling the game as 'boring'.
However, he was quick to admit his side weren't good enough and United deserved their victory.
"I think it was a boring game, no chances from both sides," Bosz said.
"We were not good enough and congratulations to Manchester United.
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Sergio Romero – 7.2
Peter Bosz reckons the Europa League final was 'boring'
Peter Bosz congratulated Manchester United on their Europa League final win
I think it was a boring game, no chances from both sides
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"We will learn a lot from this and if we keep this side together we will be stronger next year."
United's victory meant they won two trophies this season, as they lifted the EFL Cup back in February.
Mourinho meanwhile, was keen to dedicate the triumph to the victims of the Manchester terror attacks on Monday.
He said: "My thoughts are obviously with the victims of the tragedy in Manchester and with the families. The tragedy is in my mind.
"Maybe this victory will bring some happiness to Manchester, I don't know. I would obviously, me and everyone else, we would change this trophy for the people that lost their lives, that's obvious.
"But if I focus on the football side, I am really proud."