How to I get iTunes to merge partial albums into a complete album?

When I've brought a single before the album was out the album then lists all the tracks but not the single(s) already in itunes.

For example I have all tracks but track 3 is missing and displayed and played as a single and its missing if i play just the album.

Real example: I have Muse's album Black Holes and Relevations, brought Supermassive Black Hole before the Album. Now I have Black Holes as a single and tracks 1,2 4-11 but no track 3. So when I play the album either in iTunes or any of my apple devices it doesnt have a complete album.

I have a few of these uncomplete albums, it is very annoying!

Any ideas what i can do?

I have been to the iTunes store online and it already says i have purchased the missing track so it recognises that I have brought it but won't put it in its right place!

Thanks!