Show-money and proofs that he will not come here in Qatar to work but just to visit you.

Any documentation that he can show the Philippine Immigration like Affidavit of Support from you showing your capabilities to support him during his stay here.

And the most important thing is he knows how to answer the question that the Philippine Immigration might asks him, coz I tell you Philippine Immigration have always doubt on Pinoys leaving the country via a visit/tourist visa.