Complex sentence: The Rerum Novarum Center establish in the 1970s to advocate for rights and interests of workers, it expanded its work in the 1990s to include occupational injuries and care for foreign workers.
Split into simpler sentences: The Rerum Novarum Center was established in the 1970s to advocate for rights and interests of workers. It expanded its work in the 1990s to include occupational injuries and care for foreign workers.