Complex sentence: The term "Sindhi Baloch" refers to the Baloch people that originally migrated from Balochistan and Iran to Sindh and have assimilated with Sindhi people.
Split into simpler sentences: The term "Sindhi Baloch" refers to the Baloch people that migrated from Balochistan to Sindh. These tribes originally came from Iran and have assimilated with Sindhi people.