There is one rule: call until you get the answer you want. On a more serious note, if it is award travel that potentially involves several *A partners, you may need to call a few times. You can sense fairly quickly if you are working with someone who is willing to get the extra mile in searching inventory. When someone seems anxious to get you off the phone, get off the line quickly and call again.

It might also help to research yourself concerning the precise partner flights you are interested in -- carrier, date and flight number. I called in September for a C award JFK-BKK-NRT-JFK in March with the exact flights I wanted and got them all. So a little homework may help rather than expecting the agent to do it all.

That said, there is no foolproof method. It is hit or miss.