The Texans have lost three of their last four games, missing out on a bye week in the playoffs.
The head coach told reporters: "You're always trying to put your quarterback in the best possible position to be successful. And I haven't done the job that I need to do in the last month from that standpoint.
"There are things. You throw a screen, you throw a ball, we had a couple of catches [on Sunday] in the game where we should make better runs after the catch for him, maybe we would take one to the house.
"But at the same time he's got to do things better. And I'm up there searching all I can to put him in a better situation to be successful."
The Texans face the Cincinnati Bengals in the playoffs this weekend.