Why won't the photos app of W10 show all photos in an album?

[widesky867]

I transferred photos from my lumia 920 to the W10 photos app.
The frustrating thing I noticed is that when viewing individual ALBUMS, not all photos are shown? Instead, an option is given to 'Add or remove photos'.

Is there anyway to view all photos in these albums? Also any chance we can do a select all shortcut?

Thanks