When I work with browsing, I try to keep the story of Yertle the Turtle in mind. Yertle's favorite saying was, "I'm Yertle the Turtle, oh marvelous me. I am the master of all I can see. And nobody's head can see higher than me."
Each subnet has it's own Yertle, the Subnet Master Browser. This server registers a <1D> service identifier with WINS.
When a new server comes on line, the server locates its Subnet Master Brower by querying WINS for a <1D> record in its subnet. When the master browser responds, the server registers its name in the browse database.
When clients browse, they contact their Subnet Master Browser (again located via the <1D> record in WINS) to get a copy of the browse database. Windows displays this database in My Network Places or in a listing from the NET VIEW command.
The key to your question is knowing how to get the browse database from other subnets to the Subnet Master Browser.
If you have a domain, the PDC becomes Yertle, standing on the backs of the Subnet Master Browsers to see the contents of the entire domain. The PDC is the Domain Master Browser. It registers a <1B> record in WINS so that everyone knows the identity of the king.
The Subnet Master Browsers see the <1B> record in WINS and realize that someone's head is higher than theirs. They dutifully send a copy of their browse database to the Domain Master Browser. The Domain Master Browser merges all the databases and sends the result to the Subnet Master Browsers who adds the new database to its own. As a result, clients can see all the servers in the domain, even if they are on other subnets.
The Domain Master Browser also collects information about other domains by querying WINS for <1B> records from those domains. It then contacts the Domain Master Browser from those domains to get a copy of their browse databases. It merges this information with its own database and distributes this to its Subnet Master Browsers.
So, here's the short answer to your question. If you have a single WINS architecture where all servers in all domains register and resolve their name lookups, then the client should be able to see the servers in all those domains. If this is not working for you, then take a look at your WINS setup for potential design errors.
If you use NWLink as well as TCP/IP, you may get uneven results. Because there is no IPX/SPX analog to WINS, Windows uses NetBIOS broadcasts to communicate browse information. Your routers must be configured to pass Type 20 IPX packets for this to work.
Once you get browsing to work, you can go to another Dr. Seuss place, the land of Solla Sollew, "where they never have troubles, at least very few."