move vertices

In Silo I could press ctrl and move vertices. Is it something in Nvel?

There's a StreamLine tool called:
Generic Tools >> Tweak_Move.
I think there's even a built-in tool already defined that contains it.
Enter Edit->Customize->StreamLine Tools, open "Built-in Tools" branch and look for "Tweak". If it's not there, create a new tool, assign "Generic Tools >> Tweak Move" as its LMB Tool and bind CTRL shortcut to it.