Your apple music is not able to search the desired songs(song name-chalo chalein by zelliX) earlier also i had given the dfeedback for the same but still i got the same issue, so i unsubscribed the subscription i have the problem regarding search option doesn't matter i listen that song but IT SHOULD BE IN APPLE SEARCH LIST BUT ITS NOT THERE SO ITS WASTE OF MONEY.....ITS BETTER I USE YOUTUBE MUSIC AND RESSO APP