Album covers in iTunes

So I stumpled upon an interesting problem when I tried to add covers to my albums in iTunes. It seems additional information is added to the album which (I think..) prevents iTunes from finding the correct album.

Sometimes it's so simple that the album in question simply isn't available, but I tried the "Show in iTunes Store" to be sure and that's when I found the added information.. that I haven't added and can't change in any way I know.

Here are examples about two different albums, both are from the band Anthrax. I have the same situation with several other.

Here it's like iTunes tries to find an album called "Worship Music Worship". The first track is called "Worship" and here (I guess) it's been added to the title somehow.

The other example is this:

This is for the album "For All Kings"

And same here, the first track is added to the albums title which again doesn't work.

Where is this information added from and how can I change it? It's not an ID3-tag issue..

I'd appreciate any help I can get!

Thanks!