In "products" listing page I need to filter records depending upon a "brand".

# ===================================
# Filter Scope Definitions
# ===================================
scopes:

    brand:
        label: Brand
        modelClass: October\Demo\Models\Brand
        nameFrom: name
        scope: FilterBrands

If I have the brands lesser than or equal to 500 records in DB, the listing filter in product model is working good. But if I have the records more than 500 it is not working.

As you closed your issue on Github I may think you have solved your problem. that could be interesting to know what it was and how you solved it.

There is no issue in the plugin. It was a configuration problem. We solved the problem by setting the max_input_vars variable in php.ini file to a value greater than 500.

Okay, thanks for this info, should be usefull for other people.