Is spam filter too though?

Hello all,
(Licensed version)
Certain mails which I receive on my Android tablet, (same email address), do not appear in eM Client on my PC, usually from commercial companies but it’s NOT spam.
They do appear on my synchronised Gmail account too.
When I go looking for them in my spam box it’s always (!) empty, I never have seen any mail in that box ?
Any ideas ?
Thank you very much for your reply