It is from a song named 此情可问天. 倚 = lean on, 月 = moon, 歸 = return, back
So I think 青塚倚月歸 means "(She) leaned on 青塚 (watting) for moon back". The question is what is the meaning of 青塚. I know 塚 = tomb mound. I cant get the meaning of 青塚 in this sentence, 青塚 is tomb of 王昭君 so that CANT LEAN ON. does it have other meaning?