할 수 없지 (There is nothing we can do about it) : The expression “할 수 없지” is used when we give up on something which cannot be solved with our ability or effort.
보기보다 어렵네 (It is harder than it looks) : We say “보기보다 어렵다” when we find out something which looks easy when we watch, but is difficult when we actually do.
It is used when we leave from an appointed place after meeting a person, or when we leave the work place for home.
the Korean Tutor 