Since the original WannaCry malware infestation, Microsoft has moved to deprecate the old version of the Windows disk and printer sharing protocol, SMB 1.0 faster than originally planned.
Unfortunately the classic way for Windows systems to discover and browse network shares in non-Active Directory domains still used some parts of the old protocol.
The new Windows share discovery protocol for non-AD networks, WS-Discovery, is completely separate from the SMB protocol and Samba has not yet integrated support for it.
If your Windows systems have disabled SMB 1.0 (as is strongly recommended for security), and you are not using Active Directory, and your Linux systems have no software that can announce their available shares using the new protocol, then Windows systems won’t be able to find the Linux shares automatically but can still connect to them if the user knows the name/IP of the sharing host and the name of the share.
There are some projects designed to mitigate this issue until Samba manages to integrate the new protocol:
These will read Samba's configuration and will respond to WS-Discovery queries on the local network. To use these, you must allow incoming TCP connections on port 5357 and multicast (UDP) traffic on port 3702. The multicast part of the protocol uses IPv4 multicast address 18.104.22.168 and IPv6 multicast address fe02::c.
On the client side, Debian 8 may be too old to include the new browsing protocols in client-side tools.