Sam ducked the claw and moved inwards. He tried to get the sword deeper into the mouth while he moved deeper into the bear's area.
He controlled the sword with one hand while he hit the shoulder joints of the bear. It is like infighting in boxing. Trying to get into the personal space of the opponent and making it impossible for them to attack.
That is the only way for Sam to have a chance. Luckily, he is a cultivator now, and he has enough physical strength to match a bear if not more than what's needed. When he first fought it, he didn't have any of that.
He had to use a lot of tricks. But of course, he used this infighting technique even then, but with a different set of weapons and skillset.
He wore down the bear using all kinds of tricks before he managed to get in that zone and kill it.
Luckily for him, now he doesn't have to do all that and go through so much trouble.