help with pieces of memory

Hi everyone, im sure im not the only one, but i have to ask cause im loosing my sanity over this. im missing 4 pieces of memory to be able to continue to play here mode and get minato, i know the last pieces doesnt appear in maps, so ive been looking for days in every map but i havent find anything u.u, please if anyone can help with this ill be so gratefull, its been days of running and searchcing and nothing!, thx!!

Check a walkthrough. (I haven't uploaded this walkthrough nor do I claim to have made it.) gamefaqs[dot]com/ps2/937038-naruto-shippuden-ultimate-ninja-4/faqs/47786