some question about esp32 filter

[malaimo]

Due to the integration of esp32 and other radio frequency parts in our product, the esp32 has suffered severe radio frequency interference. I saw that the esp32 document stated that the module has a built-in filter. I now have two problems:
1. Are there any specifications for the filtering characteristics of the built-in filter? We need to evaluate whether the filtering characteristics meet the requirements. I did not see it in the official datasheet.
2. How to add additional filters to the module to improve the filtering performance?

Thanks!