Good attempt,
Let me add some clarifications to this:
HR Manual is also referred to as an Employee Manual. The Employee Handbook consists of a summary of the HR manual in the form of a small handbook.
An Administrative manual is a manual with procedures and systems of an administrative nature, such as Travel Expenses, TA/DA Allowance Rates, provision and maintenance of Infrastructure of the Company, including Air Conditioning, painting of Buildings, Plant and Machinery, Safety Equipment, Tendering procedures, Canteen Utilities, etc.
Company Policy is multidimensional; it depends on different business lines. For example, separate policies are declared for ISO, marketing, HR, etc. These policies are supported by Policy Objectives, Purpose, Statement of Management Intent, and guidelines to accomplish those objectives.
I hope this is clear enough to differentiate.
RashidBhai