VS CODE Search Options

Your screenshot shows the ObjectScript Explorer view, which was originally created for the client-side development paradigm in which you export to a folder on your workstation the routines/classes/etc you want to change, then manage them locally in Git. You then import your changes to the server that your `objectscript.conn` setting points to (the same place you may have exported them from).

In this case you can expand the Routines node of the tree shown in your screenshot, then with focus on that tree press Ctrl+Alt+F to invoke VS Code's tree search/filter widget. Here's a screenshot of me using this to narrow down the large number of INT routines in a VistA namespace:

The other development paradigm (server-side) may suit you better if you are migrating from InterSystems Studio.

In that paradigm, use the Servers view (at the bottom of your screenshot) to expand the Namespaces node of your server. Then use the pencil or the eye button to add to your VS Code workspace a folders that gives you direct access to the namespace (pencil if editing, eye if only viewing as read-only).

Also follow the instructions in the README of the InterSystems ObjectScript extension to enable proposed APIs.

Then type Ctrl+P and start entering the name of the routine you want:

You can also use the Ctrl+Alt+F tree widget on the VS Code Explorer view of your workspace.