Default [Q] Sony Walkman question

hi guys, my gf z1 have a issue like when she download songs from a apps, walkman showing all song but 2. I cant manage to find the 2 song in the walkman. anyhow know how to search?
Current Device: d[n_O]b
Sony Xperia Z1 C6903 [Codename: Honami](2013)
Previous Device: d[O_n]b
Samsung Galaxy Note 2 GT-N7100 -- running on Omega v17 (2012-2013)
Samsung Galaxy S4 GT-I9505 -- on Omega v12 (2013)
Samsung Galaxy S3 GT-I9300 -- on Omega v49 (2012-2013)
Samsung Galaxy Note 10.1 GT-N8000 -- on Omega v2.1 (2012)