The Scottish Premiership champions sold Stuart Armstrong and Moussa Dembele at the summer, bringing in Odsonne Edouard on a permanent deal to get a record £9m.
Rodgers admits he”failed to conceal a natural frustration well” as other registering goals were missed.
“We are assessing goals as well as the areas we must strengthen in and enhance,” said Rodgers.
“January is an important window.
“That is an ongoing matter. I’m convinced there will be discussion in January concerning that. In the meantime, the attention is.
“The guys behind the scenes are still working extremely hard, preparing for a few players to come in.”
“I’m not one that can hide it very well, I was not hiding it well at all,” said Rodgers.
“There was a natural frustration as as a manager and leader of the group, you would like to keep on pushing ahead.
“But you come away and review and reflect. What is great about my relationship with the board is that, when you work with, it is only human you won’t always agree.
“If you work closely together with folks you’re not always going to agree. What there is between us all is a huge respect.”
The Celtic manager added:”There is an unbelievable collective effort on and off the pitch out of us to be where we’re now as a team. That must be continued along with the way is by talking and communicating and planning.
However, needless to say, it is constant and in January we hope that we’re able to enhance the squad.”
‘Brown’s been top course for me, needless to say I need him to stay’
The 33-year-old midfielder is back after trauma in training and has been linked to the United States and Australia.
“He loves it here and there will be an agreement between him and the team concerning that,” said Rodgers.
“If he’s choices in this last period of his career, then he probably wants time to check at that. But no supporters should take that that he doesn’t want to be here. He’s been absolutely top course for me and we need him to stay naturally.”