Individual thumbnails for my Facebook fan page posts?

[cineweekly.com]

How do sites allow separate thumbnails for every article when you share their link on Facebook? I have fan page and all I can do is assign one thumbnail to represent my site and it shows on every single link posted.

[Grphoay]

I'm not sure I have seen a site have different thumbnails for different posts, unless what you're seeing is where they have posted a link and the thumbnail is from the site where the link came from.

[cineweekly.com]

I'm not sure I have seen a site have different thumbnails for different posts, unless what you're seeing is where they have posted a link and the thumbnail is from the site where the link came from.

That's what I mean, not their profile's thumbnail. I thought you used to be able to specify a thumbnail after you've attached a link to a post. I'm only provided the option of my meta specified thumbnail or none at all.

[Merculxik]

I've never seen the option to choose a thumbnail once I post a link.

[cineweekly.com]

I've never seen the option to choose a thumbnail once I post a link.

This is for a Youtube video instead of an html page but it's the same for an html page. I never have been given the option of another thumbnail, just the greyed out arrows: