Private Mailbox with Anonimity??

As you all know, clevvmail is very good service but has a terrible procedure.
I have read in another post that Singapore is guaranteed privacy and can use one physical address with two business names, but I can't find it now.
Does anyone know? Or can you recommend a physics mailbox that is good for maintaining anonymity?

I can go to Asian country once a month.
I don't want my mailbox provider to store my personal information.

Thanks for the answer!