Link between Service Entry Sheet and Material Document

Hi

I am busy with developing a report where i am required to find the link between the Material Document and Service Entry Sheet. 

I am aware that on the Purchase Order Data tab of the Material Document has the service entry sheet number and line item.  However the problem I have picked up here is in the event I create a Service Entry Sheet  with a service in line 1 and for some reason Delete that Line and then capture the service again, it is saved in table ESLL as line 2.  This is correct.  However when I have a look at the material document, it references it as line 1 of the service entry.  Is there any way to get this in sync?

Thanks

Vinesh