Original list:
He_is_super_hero_Spiderman
He_was_a_super_actor_Tom
This_line_is_not_supposed_to_match

Finding whole lines containing matches:
He_is_super_hero_Spiderman
He_was_a_super_actor_Tom

Finding and extracting matches:
Spiderman
Tom

Not actually looking for matches, just extracting the last word:
Spiderman
Tom
match