Search for Idocs in XI

Hi

in our scenario we have idocs being posted from xi to crm.

But the idoc numbers are different in xi and crm.

Is there any way to:

Search for a particular idoc in crm and its corresponding idoc in xi.

i mean suppose 123xxx is an idoc in crm that was posted from xi then corresponding idoc of 123xxx in XI .

Thanks in Advance.

Helpful answers would be rewarded.

Thanks,

Amith