The Cottagers have collected just five points from their last nine top flight games, sliding to 14th in the Premier League as they attempt to cope with a series of fitness problems.
Jol, though, remains wary of being pushed into rash decisions in the market in a bid to strengthen his squad for the second half of the season.
|28/1||Fulham are 28/1 to win the FA Cup with Bet365|
"You know as well as I do that clubs will wait and wait until you have to pay the maximum price and we will not do that."
Fulham could be boosted by the imminent returns of midfielder Mahamadou Diarra, forward Mladen Petric and winger Damien Duff, with playmaker Bryan Ruiz having already made his comeback after hamstring problem.
"If players come back from injury, I think that will freshen up the squad as well," Jol added.