# Filtering an expression: keeping only term with even power

In the expression $$ x^2 y^2+x y^2+x^3y + 5 x^4 y^4 $$ I would like to keep only the term where the variables have even power $$ x^2y^2+5 x^4 y^4 $$

Is there a way to do it?

I look into this post.

But once I get the operands, I don't see how to analyze the variable exponent.