Complex sentence: Since, they have become one of the most successful producers of serials in the channel and some of there biggest successes was their daily soaps Kolangal, Thendral, Thirumathi Selvam, Priyamanaval in Sun TV being the most viewed South Indian TV program during their broadcast.
Split into simpler sentences: Since, they have become one of the most successful producers of serials in the channel with popular daily soaps Kolangal, Thendral and Thirumathi Selvam. Priyamanaval on Sun TV is the most viewed South Indian TV program during their broadcast.