The Sunderland loanee has not scored in his last 21 games, spanning across three clubs - Swansea, the Black Cats and now Hull - and he was wildly off target in a 1-1 draw with Malky Mackay's men at the KC Stadium.
He smashed over the bar of an open goal from eight yards with six minutes on the clock and then ended the game with a poor miss with a header which barely tested Joe Lewis in the Cardiff goal.
The 28-year-old last scored a goal of any description in Swansea's Capital One Cup win over Chelsea on January 9, but manager Bruce is not ready to give up on the player who Sunderland paid £6million for just a matter of months ago.
"He has got to stay at it," said Bruce, who, aware of Hull's anaemic front line, made a late and ultimately unsuccessful deadline-day move for West Brom's Shane Long.
"Danny has to stay strong. I just spoke to him about that. If you're a striker, you go through these spells. You don't lose your ability, but you have to stay strong. That's the Premier League, it's tough.
"I'm not going to single anyone out. A striker is judged on goals. He's finding it difficult but perhaps that's why he's here. He needs one to settle him down. Perhaps he's trying too hard because his overall game was terrific. He needs one to go in off his backside.
"Who knows, he could go and score the winner against Newcastle next week."
There would be a certain irony to that for Graham is a lifelong Newcastle fan, although Hull need the goals to come from anywhere they can get them.
Last year's elevation from the Championship was in spite of their forwards rather than down to them and a lack of final-third punch was clear again.
Source: PA
Source: PA