Correct fixings for plaster wall with solid wall behind

[kgeoff]

Hi again, can someone tell me what fixings i should use on my wall. There is plasterboard to begin with then a small gap and then what appears to be solid wall. I have a large fitting that needs to be fixed so ideally should go past the plaster and into the wall. My dilemma is how can I get a wall plug into the brick as i can't get a hammer past the initial plasterboard? Thank you

 

[AlanE]

Screw wall plug onto longish screw and push plug, on end of screw, through plasterboard and into wall.

Then gently hammer plug into wall by hammering on end of the longish screw.