There are a few ways, but the one I would use is, ensure the Delta x, y and possibly z fields are on the inspection bar, if not, click selector properties (first icon right of inspection bar fields) and under whatever section you are working in, 2D or 3D, tick Delta x and Delta y (I always have all three permanently ticked.)
Then select two of the circles, the reference point should automatically be in the right place (centre of extents). and, say I wanted to move them 10mm closer horizontally, I'd type -10 in the delta x field.
As I say that's just one way, I find the delta fields very handy #### Assuming your version of TC does have these fields available ######
Ignore the above if I have misunderstood your requirement.