How to solve the problem with filtering variable products by attributes?

Question

WordPress

There is a site wheelsnheels.ru
The site has a problem with filtering variable products by attributes.
Each disc has parameters - diameter, width, drilling, overhang
For example, in one Black Rhino Taupo variable product there are variations
Diameter 17, 18, 20
There are widths 8.9
Diameter 17 and 20 has a variation with the 9th width
Diameter 18 has a variation with the 8th width
The problem is that when you enter the required selection Diameter 18 - Width 9 (as well as selection 17 diameter with a width 8) in the filter, this product drops out in the results, although it should not.
At first I thought that the problem was in the general sku for the entire variable product, I corrected the sku for unique ones for each variation - the situation has not changed.
I would be very grateful for any help.