The Italian high-flyers lost twice in the space of a week, beaten 2-0 by Serie A rivals Napoli on November 1 and 2-0 at Bayern Munich in the UEFA Champions League four days later.
But Roma returned to form on Sunday, with Vasilis Torosidis, Seydou Keita and Adem Ljajic on target in a 3-0 win over Torino at the Stadio Olimpico.
Roma remain second in the Serie A standings, three points adrift of defending champions Juventus, and Garcia insisted he has full belief in his squad as he eyes long-term success.
"I have always been relaxed. I said yesterday that I have faith in this Roma and my lads," Garcia told Sky Sport Italia.
"We won playing our usual football with possession, enthusiasm and movement.
"We were in better shape physically and scored some great goals.
"I said it's not just one or two games that change everything. We've been working on this project for 16 months and it is to build something long-term."
Netherlands international midfielder Kevin Strootman made his first appearance in eight months for Roma.
Strootman came off the bench in the 84th minute as he took to the field for the first time since tearing a cruciate ligament in his left knee against Napoli in March.
"Kevin became a player again tonight that was the most important thing," Garcia added.
"He's not 100 per cent, but the fact he's here at all gives us joy. He got to play about 10 minutes and enjoyed them."
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