This is what i did and now i can see my files in internal storage:
I started from O based Xiaomi.eu ROM.
1) Rebooted to this TWRP https://mega.nz/#!bV1zSaKL!U3Ot4vhj35hg2Ti2z96cHy0RsNMYBIL5hmnQedu2Ybc
2) Wiped cache, dalvik, system, data and internal storage
3) Formatted internal storage
4)...