Zoho Books HIPAA compliance

Zoho Books HIPAA compliance

I understand that Zoho has legal documentation of their HIPAA compliance (as seen in CRM thread from 6 years ago). 
For a medical services company looking at Zoho Books:
  • where is this documentation located?
  • specific to Zoho Books (only), is the customer data and their invoice details covered under that compliance?
Any other users have insight on this much appreciated!