Idiomatic two- or three-word (or phrasal) verbs usually combine a verb with a word that appears to be a preposition or an adverb (called a particle). The combined meaning cannot be understood literally, and similar expressions often have very different meanings.
hand in means “submit”
hand out means “distribute”
look into means “investigate”
look out for means “watch carefully”
run away means “leave without warning”
run into means “meet by chance”
walk out on means “abandon”
want out means “desire to be free of responsibility”
Native speakers of English will notice misuses of these idiomatic verbs even though they use the verbs without thinking about their literal meanings. When you are unsure of the meaning or usage of such verbs, consult a dictionary or ask a native speaker.