As yung_lean said, '자나' is a misspelling of '잖아,' which is the verb suffix for something that the listener already knows. Adding '도' to the verb gives it the meaning of 'even though (verb).' V + '고싶다' means 'want to V.' '못' is a particle which changes the sentence to mean that you are unable to do the verb. '보다' is the verb meaning 'to see' and is used in both clauses of the sentence. The sentence is literally 'Even though (I) want to see (you), as you know (I) can't see (you)." A better, more natural translation would be "I miss you, but I can't see you."