Okay, I saw another question like this before. I cant write an essay for you. But I can give you pointers and tips.
In "Cranes," just after Song-sam lets his friend escape, he hears a shot.
This is the moment when he becomes very worried about his friend, because he starts thinking that maybe that bullet ended up in his friend, hurting, or possibly killing him. He wants to find out what happened which is why he ventures forth.