Complex sentence: Sindh also had Hindus and Sikhs population of 25% at time of independence of West Pakistan, most of them migrated to India, many of them remigrated from India to the other parts of the world.
Split into simpler sentences: Sindh also had Hindu and Sikh populations of 25% at the time of independence of West Pakistan. Most of them migrated to India, many of them remigrated from India to the other parts of the world.