Windows Explorer Search from remote subnet

I cannot search a network drive from Windows Explorer unless my computer is
located in the local subnet of the server. I also cannot search a share on
the server from a remote subnet. However, I can search from a command prompt
on a computer that is in the remote subnets.

I do not have any problem accessing the network drive or opening any of the
files on the network drive. I also do not have a problem searching for a
computer or the server from a remote subnet.

The subnets are connected through a Sonicwall VPN connection. NetBIOS and
fragmented packets are allowed to pass through the VPN connection. NetBIOS
Over TCP/IP is also enabled on the computers and on the server.

Does anyone have any suggestions as to why we can't search a mapped drive.