PO Trackablity Blank Title 52401

Not sure if anyone can help me out with a problem were having - We are
using Vista 6.10 version 538 and below is our problem:

We have several customers that issue anywhere from 2-12 purchase orders
for (1) project (Machine) We are taking out one sales order and adding
lines for each purchase order the customer is issuing we are referencing
each PO under line release since the sales order header only allows for
only 1-PO # to be listed. We have a hard time looking up/tracking the
other PO's that were assigned to project (for example when the customer
calls and questions where were at on project and only gives us a PO #
that's not listed in header). If any one has an idea - I'd love to
hear them.

Thank you
Cathy Wollpert
Lomar Machine & Tool