Hi @ibieee

As far as I know, minimum of 3 stamps required on a legal document:

1. Ministry of Foreign Affair (your home country)
2. Qatar Embassy in your home country.
3. Ministry of Foreign Affair Qatar.

If it is an education certificate, attestation from Ministry of Higher Education in your home country is required too. To get this certificate attest by MoFA Qatar, a bonafide letter are required to be attested by above mentioned department followed by MoHE too.

Hope this help.