Complex sentence: Two search parties were dispatched in the spring 1903, one of them searched the shores of the New Siberian Islands and the other, led by A.V.Kolchak, travelled by whaleboat to Bennet Island.
Split into simpler sentences: Two search parties were dispatched in the spring 1903. One of them searched the shores of the New Siberian Islands and the other, led by A.V.Kolchak, travelled by whaleboat to Bennet Island.