Plot of a line between two points in 3D

Hello,

I need to plot a line that describe the electric field between two points in 3D. I tried the way I used to try in 2 D but obviously it didn't work as I wanted. It didn't give me the plot I expected. I thought the reason was that when I click the point it does not penetrate the surface. So all the plots that I could do is on the surface. This is not what I want. I want a point from the core of the sphere to half of the cylinder.


Attached is my model, the expected plot and the wrong plot I am getting.


Do you know how I can penetrate the surface and generate a plot from a point in the core to any point from the cylinder?

I'd really appreciate any insight :)



Thank you.