You already know how to do this, you just don't realize it.

How do you find files with an "x" in their name? That's right, you use dir *x*.

Now you just have to change that x to a space. And since spaces are command line delimiters, you need to quote the sequence so it gets treated as a single parameter rather than two "*" parameters:

dir "* *"

Stick in a /s if you want to search recursively.