I'm an engineer. How do I improve my communication skills?

[Mario]

I just graduated with an engineering degree and I have a good GPA. I have only done one internship but it should have been more if only I'm good at communicating. Employers would call me for an interview and I would never hear back from them after. I have had 24 job interviews over my college career and only one actually gave me an offer. English is not my native language but I don't have an accent. I'm just bad at expressing myself at times. But I am actually very serious in everything that I do. It is really depressing as I see my classmates who didn't even worked that hard in college are getting job offers and I may just end up keeping my job as a cashier at Walmart. :-(