The victory at Mestalla takes the Blaugrana to within two points of leaders Atletico in the table in LaLiga Santander, with the pair meeting at the Camp Nou next Saturday.
"It will be very close, that's also what we hoped in January," Schreuder said on the title race.
"We are there. We don't have to look at other teams. We look at ourselves.
"Sometimes we lose points, sometimes Atletico, sometimes Real, Sevilla... It won't be the final game next week. We still have four games to go.
"Everybody at Barcelona trusts our players [to win the title]. We trust our players. That's what they showed today again.
"If you look at how far the distance to Atletico was in the beginning, in January, it was very far.
"We've had a very good month for the last three months. That was important to be where we are now.
"If we win next week, we are above them.
"We look at game to game. Of course, we know that it's a very important game [against] Atletico."