Permission Issue in Windows2003

Hi

I have a folder and under it many child folders are created. This folder has been given full access right for domain admin and to users. User can access all file and folders created by him. As as domain admin i can not access some of the childs folder and files. When taken ownership i can access these folder and files inside it.
Can anyone tell be what i am missing in permission. How permission can be propgate downwards.

Thanks & Regards
Siddhpal Patel