any bus from guangzhou airport to nanning after 14.45?

But no direct bus from the airport to Nanning is available. If you don't mind, I know there are airplanes to Nanning after 14:45 for your choices. Sometimes, the air ticket enjoys great discounts.

If you prefer to travel by bus, take shuttle bus line 1 to CAAC ticket office. Then walk to GZ Provincial Bus Station to catch a bus to Nanning. Buses for the trip are scheduled from 07:45 to 23:30, so you will catch one.