Help filtering MySQL result with first name and last name in different table columns

Hello Wapplers,
I am stuck, I’m trying to filter a mysql query where first name and last name is in different columns with only one text field. When filtering on first name it works and also last name works.
But when searching for “firstname lastname” i can’t get it to work.

At the moment this is my filter:

image753×329 25.9 KB

Any guidance would be much appreciated.

Cheers!