"We've got to improve in what we do with the ball," Bruce told BBC WM.
"But the big problem is we don't score enough. That is our big Achilles heel."
Speaking after Saturday's 1-0 home defeat by Ipswich Town, he added: "One individual error cost us in a game we didn't deserve to lose. We're not scoring and we're getting punished at the other end."
Bruce said: "I've seen glimpses of them that they'll be ok, so we have to stay with it.
"Nobody envisaged that Aston Villa would be in the bottom half of the Championship. But that's where we're at. We have to batten down the hatches and keep plodding away.
"We've lost the home record which we were clinging on to. But we need to turn it round quickly. Now can we go and get a result on Tuesday?"