anime tv shows not showing up as series on iPad mini

when I put the anime series I downloaded into my iPad mini 3 it does not get sorted by series. It goes into random sorting and all the series are mixed together into one. But on iTunes everything is properly sorted by series. I looked at other questions similar to this and when i go to the info section i do not have the same options (like the track number), so It isn't being sorted properly. How can i fix this!