Who can help with a small wordpress - php - xml problem

Hello,

I'm working on a wordpress site, On one page there is a simple form with php searching in a xml file.
That is working fine. If you type a character it will give you some result

On another page I need a second search form searching in another xml file. I can't get this working, but i'm not a programmer.

https://cott.nl/villa/artists/
find a artist - is working fine!

https://cott.nl/villa/shop/
here i want the same thing, but then searching in another xml file

I hope someone can help

cott