How can I see all of my iTunes songs on my laptop?

[iMore Question]

Itunes and songs

Hello.. I have 16 gb Iphone 5s and I have currently 223 songs on Itunes on laptop and on my Iphone. The problem is: when I try to add new songs on Itunes on laptop, they don't display, and it still says that I have only 223 songs, but I added a few more. Why is that? memory? Something's wrong? Please help. Thank you.<3