How to score more...

phng4

I use Juventus with 4-4-2 (winger). I always have 1x shots on goal but only can score one or even nil. How can I improve this situation?
Also, the MCs always gets 6-7 on average... Why is that??
I attach my tactics and here are my players:
Del Piero  Amauri
Cani  M.Fernandez  C.Zan  Camoranesi
Chiellini  Andrade  Barzagli  Zebina