How do we know and track what System Administrators have done within the system?

Content

Our internal and external auditors have flagged up an issue around System Administrators within the Oracle Cloud ERP system - how do we know and track what they have done within the system? Are there audit reports for these types of roles - as these users typically have 'powerful' access so could in theory make lots of changes. 

As far as we can see the Audit functionality within Oracle Financials cloud, configured in Manage Audit Policies, is based on the product and not the user. And the delivered reporting is limited and would not allow us to report on all changes done in the system by a certain user or users which certain roles.