Unable to find Purchase Order created from Sourcing

Hi everyone,

I'm dealing with Oracle Sourcing release 11.5.10.2. 

I created a purchase order from sourcing and I would like find some way to find this in PO using the negotiation number. Is this possible?

If the Negotiation was created from a requisition I know I could find it with the requisition number. But, what happens if not?  Even, if I have the idea to have a traceability of the process I would need this. Neither i'm not able to see in the purchase order the negotiation number from where the purchase order was created.  Have been this function thought-out in Sourcing? I don´t know if there is something is missing to set up.