The Magpies face Nuno Espírito Santo's Wolves at St. James' Park on Sunday afternoon (kick-off 2pm GMT) but will be without the services of Schär and Carroll, who both picked up injury problems in United's 1-0 defeat against Chelsea last week.
Furthermore, midfielder Isaac Hayden will serve the final game of his three-match suspension while French defender Florian Lejeune and wide-man Matt Ritchie are nearing returns to the first team squad but will also be unavailable for the Premier league clash.
"They're not serious at all," Bruce said. "Unfortunately, Andy picked up a groin strain last Saturday and Fab has had a sore knee that he's been playing with for a few weeks and last Saturday became too uncomfortable for him.
"So they'll both miss tomorrow but they could be in contention for next week (against West Ham United). We expect them not to be long term which is good news.
"It is part and parcel of football - that's why we have the squads that we have, especially in today's game. You are going to pick up injuries and just when you think you had a clean bill of health, you pick up a couple.
"The good news is that Flo (Lejeune) is close to a return and so is Matt Ritchie. He's been bouncing around the training ground all week so it's good to see him back as well."
Goalkeeper Martin Dúbravka committed his future to the Magpies this week after the Slovakian signed a new six-year deal at the club.
And Bruce expressed his delight in securing the long term contract of Newcastle United's number one, who has kept three clean sheets in the top-flight so far this term.
The 58-year-old added: “We want to tie down our best players. Martin has had a wonderful few months since he's been at the club and has been rewarded. In that respect, we're all delighted.
"He’s a very, very good goalkeeper. We’ve unearthed one, because not a lot of people had heard of him and it's essential for any big club. You need a good goalkeeper and we’re delighted that he’s tied himself to the club.”
United could join Wolves on 11 points with a victory on Sunday, who currently sit in 13th place and are enjoying a seven-game unbeaten streak in all competitions, which includes an impressive 2-0 away victory against Premier League champions Manchester City.
However, Nuno's side travelled to Slovakia on Thursday to face Slovan Bratislava in the Europa League group stages and Bruce is hopeful of taking advantage on their opponents' European expedition.
He added: "That's always a difficulty of it. I experienced it at Hull a few seasons ago and it's mightily difficult to get that mindset of playing on Thursday because you'd always play on a Sunday. The big teams who are used to playing repeatedly in Europe become accustomed to it but it can be difficult and I hope we can benefit from it.
"They're a very good side so if they are a bit fatigued, hopefully we can take advantage of it. We're at home against a very decent Wolves side but we're capable - we know that - and we'll have to play at our best to win but we're quietly confident we can do it.
"I can only be quietly impressed of what they've done. They romped the Championship a couple of years ago and finished seventh in the Premier League last year.
"They've got some good players and play in a certain system and do it very well. They're a threat and a good side who have already played 19 games this year and only lost a few."
