Hi Anjali,
In QTP, Synchronization is nothing but Time mapping between Tool and Build. In QTP default timeout is 20sec. There are 3ways to change time mapping.

1. By changing the default timeout to our desire time
File menu--> Setting--> Run Tab--> Change timeout from 20 sec to more--> Click Apply--> Click OK.

2. By using Wait function.
wait(time in sec)

3. Inserting Synchronization point on Process completion Indicator Objects in Build
Ex: Status bar, Progress bar
Navigation: Select Positon in Test--> Insert menu--> Sunchronization point--> select indicator object--> click OK after conformation--> enter enabled property as TRUE--> specify max time to wait in milli sec--> Click OK.

With Cheers,
Prashanth.