Complex sentence: The Hawazin and the Otaibah complement each other, to a substantial degree, in the sciences of genealogy; furthermore, the Hawazin were valued as an invaluable part of the Qaysites.
Split into simpler sentences: The Hawazin and the Otaibah complement each other, to a substantial degree in the sciences of genealogy. Furthermore, the Hawazin were valued as an unbreakable part of the Qaysites.