Complex sentence: In July 1634, officials acting on order of the King had seized Coke's papers, and between then and a 1641 motion in the House of Commons restoring those papers that could be found to Coke's eldest son, nobody knows precisely what happened to them.
Split into simpler sentences: In July 1634, officials acting on order of the King had seized Coke's papers. Until a 1641 motion in the House of Commons restoring those papers that could be found to Coke's eldest son, nobody knows precisely what happened to them.