iTunes won't add new music to library

Really strange....never had this happen before but I'm importing some music off an old hard drive that I found in the garage a few days ago but a lot of the music won't import when I try.

iTunes appears that it imports it but it doesn't show up, they're all MP3 format. I can right click them and open them in another program such as VLC but they won't play/import into iTunes. This is happening for multiple albums and I have NO idea why.

Anybody ever experience this and if so, how to fix it?

Thanks