The Grappling skill was a trump card Wang Baole learned when he was at the Ancient Martial realm. He earned quite a name for himself through the Ancient Martial Arts, regardless of whether it was when he pried the hands of a beast or when he kicked and came up empty-handed.
Even now, with him reaching Foundation Establishment realm, those three trump cards were still effective to a certain extent. Wang Baole hadn't met anyone who was able to escape from his grasp if he were to unleash the three trump cards unless there was a great difference in their cultivation levels.