Chelsea are not performing well against weak opponents. Against Manchester City, Arsenal, United and Newcastle, Chelsea are unlikely to do well and pick up points. Coach Pochettino must find his squad's weaknesses very quickly. A plus point for Chelsea is that they are not performing in the Champions League or the Europa League. They will have an opportunity to focus only on the Premier League. The team has enough time and opportunity to do well in the Premier League. However, it is Poch's fault if coach Pochettino fails to capitalize on this opportunity. But with the way they have performed so far, it seems unlikely that the team will get to the top of the table or stabilize very soon.
Chelsea just didn't have much luck, Jackson's chance hit the post, Gallagher's chance was saved by Neto. So, in my opinion, Chelsea just lacks the luck factor, this is the same as when Chelsea played against Nottingham Forest before, Chelsea also had a few more chances and the finishing was still very blunt and lacked luck.
It's true, as you said, Pochettino must immediately find the squad's weaknesses and must focus on the front line to be effective in scoring goals when he gets the opportunity. Actually, Chelsea this season should be more consistent in the EPL because they don't have a busy schedule because there is no European competition, they can focus on improving their squad to be able to compete in the EPL. I think Pochettino can handle it in the next match, and I believe in the process, he will make Chelsea become a top team in the EPL again.