Right, you can't "browse" the list of volumes, but if you know the path to your shared data, you can do it:
cluster01::> node run -node cluster01-01
Type 'exit' or 'Ctrl-D' to return to the CLI
cluster01-01> priv set advanced
Warning: These advanced commands are potentially dangerous; use
them only when directed to do so by NetApp
personnel.
cluster01-01*> ls /vol/dfs_doc/DOC
.
..
.DS_Store
Acct
Agile Development
AnalogGroup
In this example the volume name is 'dfs_doc' and the CIFS share under this is 'DOC'
Here's another, this one is used for Unix homedirs"
cluster01-01*> ls /vol/homedirs/home
.
..
jsmith
mdamon
bgates
So it sounds like you just need a little more depth to your ls command and it should work.
One last example with ls -l and a volume containing a single LUN:
cluster01-01*> ls -l /vol/netbot
d755 64 2 4096 Mon Dec 14 23:24:09 EST 2015 .
d755 64 2 4096 Mon Dec 14 23:24:09 EST 2015 ..
10600 96 1 5497629096960 Thu Apr 28 14:26:53 EDT 2016 netbot