ps_facetedsearch customisation

[LamineDistro]

hi everyone, hope u r doing well

i'm using the module ps_facetedsearch but  it s not responding to all my needs, so my challange is to customise the module.

the first thing i want to do is to change or modify the sql request that doing all this magic stuff, but i can not find it. this module is a little bit complex..

anyone to tell me where to find the sql request or the function to do that??

 PS: i  m using  the 3.5.0 version

thank you