What is Ishi searching for when he travels throughout the Yahi world?

When Ishi travels through the Yahi world, he is looking for evidence of the Lost Ones, his family who have passed away. When he first went into the cave for his long sleep, he often heard the voices of his loved ones and wandered about trying to follow them. Now, he sets out to discover whether their spirits have been able to find the Land of the Dead. When he finds no Spirit Presence at any of the old landmarks, he realizes that he is the only Yahi who is not in the Land of the Dead.