Well, you might find a good man in a short story by noticing his honesty and integrity in the situations he faces. Also, how he treats those around him, especially when it's tough, can be a clue.
One way could be to look for characters who show kindness and compassion towards others.
To find a good man in a short story, pay attention to his actions and decisions. Does he put others' needs before his own? Does he stand up for what's right even when it's difficult? These can all indicate a good man.