Best I have used out the mainstream range, tcut etc. Really depends how deep it is though and if you are through the clear or not.
Depending on how damaged the paint is, you can use a compound, such as, Meguiar's Ultimate Compound to restore the faded clear coat.
However, if your clear coat is flaking or missing, then there is no way to restore it, the solution would be to have the area or car repainted.
Like this one? MEGUIAR'S G17216EU Rimuovi Graffi Ultimate Compound, 450 ml https://www.amazon.it/dp/B002KKCLO6/ref=cm_sw_r_cp_api_glc_i_0FVBB5SDGFTCGA74NTNC