Routes with 2 variables CI3

Hello. I need something like this:

$route['controller1/function'] = 'controller2/funtion/var1=thing/var2=otherthing';

But it doesn't work.


$route['controller1/function'] = 'controller2/funtion/thing/otherthing';

Doesn't work.
The thing is: I want to modify de values of privates attributes inside the controller so it works in several ways based on the URL.