Easy.
Your pic (I think) shows the bolt protruding off the handle, and you get to the head by prising off the small plastic cover at the end of the handle.
A couple of things spring to mind, though...
The standard bolt is a 'shear' bolt - the hex head disappears at the factory once its been tightened up on the door and all you are left with is a little dimpled head - which you cant reuse easily.
But if you are not too fussed then a standard M8(I think?) bolt will do the same job and will still fit in the handle OK.
If the existing bolt has been pulled out of the door then it could be that the thread on the 'nut' portion in the door body may be stripped and the walls of these nuts are thin - so you cant fit helicoils etc.
But you can fit 'clinchnuts' - which is whats originally in the door.
Jon
