Hello guys , i have some problem about Network pentest.I read lots of security books for 1 year and i am working to be Network Security intern in a bank but i don’t think i am improving my self.I have created my own security lab in virtual box.I installed metasploitable and i am trying to find vulnerable on.But this isn’t improve anymore me.How can i do to improve me about Network Pentest.I am waiting your advice 
(Sorry for bad english)