Complex sentence: Petra Sancta provided preliminary comprehensive studies on his heraldic work in Germany and the Netherlands and that it's very likely that he was acquainted with the idea of hatching and the earlier existing hatching methods from the Dutch engravers before he developed his own hatching system.
Split into simpler sentences: Petra Sancta provided preliminary comprehensive studies on his heraldic work in Germany and the Netherlands. It is likely that he was acquainted with the idea of hatching and the earlier existing hatching methods from the Dutch engravers before he developed his own hatching system.