Unable to read email raw files

I am trying to manually back up my email files from my hosting. I went to the mail folder on my hosting server and downloaded everything. However the files that I got have very long names, the such of (I removed some letters):

17146858.M173427P6855.box5338.bluehost.com,S=7421,W=75005_2,SZ

The files have no extensions.

When I tried to add the .eml extension to the files and open them in a text editor or an email client like thunderbird, all I got was symbols and no actual text.

How can I read my emails or convert them to something readable?

here is the screenshot of the symbols when I open the renamed eml file in outlook:

enter image description here