Using "within" w/ variables

Hey Everyone, 
I’m trying to dynamically use the “within” function to filter search results. 

I have two floats, as variables: 

thing1: -400;

thing2: 400;

Basically, I’m trying to achieve:

"select x, y,z from Table where z within thing1 thing2

I’m relatively familiar with the “within” function, but have never tried to do it like this. Typically I hardcode the variables directly into the select statement so I’m not really sure what I could be doing wrong.

Anything jump out at anyone?

Thanks!

select x, y,z from Table where z within (thing1;thing2)

That was it, thanks!