How to restore my videos because I think I accidentally deleted after the updates for iOS5

Wong Ling Siew Nazurah hace 9 años actualizado por zgx hace 9 años 1
Having headache now cos i'd downloaded a number of videos which are my favourites and it's quite impossible for me to re-download it back, any suggestions for this??? Thank you.. 
If the videos were deleted manually, them can not be restored.