My oracle application test instance is down, When I browse through the Unix server, I couldn’t find any files in the mount point,U01 U06 or U10, when I put BDF command it shows the following

$ bdf
Filesystem                kbytes    used   avail %used Mounted on
/dev/vg00/lvol3           204800   35571  158662   18% /
/dev/vg00/lvol1           299157   38506  230735   14% /stand
/dev/vg00/lvol8          1392640 1261068  123620   91% /var
/dev/vg00/lvol7          1327104  825170  470631   64% /usr
/dev/vg00/lvol4           716800  385891  310746   55% /tmp
/dev/vg00/lvol6           872448  814943   53936   94% /opt
/dev/vg00/lvolssh          32768   13243   18306   42% /opt/openssh
/dev/vg00/lvol5           204800  187397   16334   92% /home
/dev/vg00/lvolback        512000  472879   36704   93% /backup
dg-ora04:/dgora03_u10     204800  167088   35416   83% /u10
dg-ora04:/dgora03_u06     204800  167088   35416   83% /u06
dg-ora04:/dgora03_u01     204800  167088   35416   83% /u01

Why can't I see any files inside the mount points?