The Toffees sit 12th after winning only one of their last six league games and were nine points adrift of the top four ahead of this weekend's round of fixtures.
Barry told Press Association Sport: "The Christmas period's always important
What we need to do is try to put a run of games together
If you can win three or four in a row, you're going to shoot right up the league.
"Unfortunately the Premier League's been a bit up and down so far
It's always difficult to put your finger on one reason but we're working hard to put it right."
The big difference from last season, when they were consistently in and around the top four, is the extra games they have played in the Europa League.
But manager Roberto Martinez had the chance to rest virtually all of his first-choice side for the visit of Krasnodar on Thursday, with Everton already guaranteed top spot in Group H.
With the clash against QPR not until Monday, the players will have had the rare luxury of more than a week without a game.
"Of course it will help," said Barry
"We had three games in six days last week so it was important that the lads that will be playing on Monday got the rest in so they can be fresh and hopefully picking up three points against QPR.
"As a club we want to be playing European football regularly and getting used to that
We've said the extra games won't be an excuse, we've got the squad to cope with it."
Barry was the one first-choice player to feature against Krasnodar because he is suspended for Monday's game.
Martinez selected a very youthful side, with four teenagers making their debuts and several more on the bench.
Seventeen-year-old Ryan Ledson, who could be the long-term successor to Barry in midfield, caught the eye, and the 33-year-old was impressed by the debutants.
"It was a chance for a few young players to show what they can do and for me it was important to get some more fitness after three weeks out," said Barry
"I'm suspended on Monday so I was happy to go out there and enjoy the game.
"I think the young players did very well
It's always difficult when there's four or five going in together.
"When you come in on your own with the rest of the team experienced, it's a lot easier, but they coped with it well and in the second half I felt they grew in confidence and the game improved.
"It's a fantastic learning curve for them, the whole day really
The lads seemed to enjoy it.
"There's a great group who are working hard together with David Unsworth in the under-21s
There were more of them on the bench that unfortunately didn't get a game, and more that weren't involved.
"There's a big number of players that have got a great chance to have a big future."
Everton have a strong track record of giving youth a chance and the majority of the academy graduates in the squad against Krasnodar come from the local area.
At 21, Ross Barkley is the latest example of the path the best young players could take at Goodison Park.
Barry added: "It's getting harder and harder for young players to break through, especially in the Premier League, but they've got a top manager here who's going to give them their chance if they deserve it."
Source : PA
Source: PA