Thank you CC, it seems you are good at training routines
Until now I was doing this leg routine.
1.Leg extensions 4x15-20
2.Squats 40x15-20
3. 45° Leg Press
4.Lever Lying Leg Curl
and 2 ex for calves at 20 reps each set

Then I started doing some drop sets for quads like this
1. Leg extensions 5 sets where I decrease weight after each 10 reps and I am doing 5 sets in one set. Hope I explained clearly

So I am not sure if coming back to many reps in simple sets will help with making that middle muscle to be shown as I have only both lateral which are big enough but there are 4 so I want to see all of them.
Sure I will start posing after each set to help with striation.