restore db from network drive

Method1:
Use UNC names: \\servername\sharename\foldername\file.ext. The
account doing the backups - which is to say the account under which
SQL Server is running - needs appropriate rights to the share.

Method2:
In the management studio; go to query window and use RESTORE DATABASE
command. Make sure that you start sql server service using
a domain account which has access to remote share.

RESTORE DATABASE <DBNAME> FROM DISK='\\Servername\Share\filename.bak' with 
stats=5