walla means boy in songs( ولا ) a singer can say it to call the one he she loves as slang harami means thief ( حرامى )not literal meaning as if u say stole my heart omri leek ( عمرى ليك )means my life is for you

by the way these words are informal in the egyptian dialect ,"wala " is very informal , it is something like "dude" in english!. and "harami" for example can't be used in formal arabic ,