Jol's side have slipped to within six points of the Premier League relegation zone having won just two league fixtures since the start of November.
They travel to face Manchester United in the fourth round of the FA Cup on Saturday with Jol revealing focus on top flight survival is paramount for the Cottagers, even if he does not have the resources to rest his key players.
"The league is the priority but we can't play different teams," he said.
"You won't see the priorities in my decision making on the teams because we still play the same team - there is not a lot of difference."
With the January transfer window still open the chance for Jol to bolster his squad remains and it is something the former Tottenham boss is interested in.
He said: "I've said a couple of times, and it is such a cliché, that we would like to strengthen the squad because we lack a few players.
"When I would like to rest players, there are some positions where I have to play the same players all the time so, of course, if we can strengthen the squad, we will do it."
Saturday's opponents United are currently five points clear at the top of the table but it remains to be seen how seriously Sir Alex Ferguson's hunt for a first FA Cup success since 2004 is taken.
Jol believes any side, no matter their stature within the game, will target FA Cup success but admits he does not know where the competition will rank alongside United's quest for success in both the Premier League and Champions League.
"When you see the starting line-up against us on Saturday we will see what their thinking is," he said.
"I think the FA Cup is important to any club and that it is important to them as well so I can't see them doing strange things.
"Maybe they'll play a different team but, if you look at their players, their squad, you won't see the difference anyway."
There is a high probability that Ferguson will give some of his fringe players the chance to impress against Fulham but Jol does not expect that to make progression into the fifth round any easier for his side.
"They're still top of the league and they're a top side with so many options," said Jol.
"Even in their forward line they've got four strikers so you have to do well to contain them but still try to do something yourself and create chances and score goals."
Fulham ran United close in their league encounter at Old Trafford back in August, eventually losing 3-2 after an early Damien Duff goal had given them the lead.
The Red Devils have conceded 11 more goals than second-placed Manchester City but have been lethal in front of goal themselves.
Jol reckons their occasionally shaky defence is something that can be targeted but knows with the likes of Robin van Persie, Wayne Rooney and Javier Hernandez United also pose a threat in attack.
"This season they concede more goals - not lately - but before that they conceded a lot of goals, but they score always," he said.
"It's a bit of a Dutch principle - score more goals than your opposition."