How to nudge prospects over the fence?

Hi, n00b here,

In my 2nd week, after blasting some emails and get pretty good response rate, there's around 10% who salesloft showed opened my email several time.

Is there a way to nudge them over replying? I tried calling (not connected) and follow up email (with a simple "thoughts") but they didn't seem to budge.

A NO is as good as a YES in this case.