If you want to see all core and library files which are used in your project, these can easily be exposed using the vMicro > Show/Hide Hidden Files button. This is very useful when trying to understand the underlying code of your entire project.
Once the menu button is pressed, you will see additional links in the solution explorer view, beneath the _micro-api-readonly folder, with links to all core, and library files in use in your project. To remove these links again, simply press the menu button again and they will be removed from the solution explorer.
When changing the board selection, all links to the core and library files will be updated to the current platform, so they are always current for your setup.
If you edit any of the library or core files opened from these links, this will directly edit the origonal copy of the code, which may be lost when performing updates in the future.
To work on a copy of a library see this page, for more information on using Shared Library projects, and the Publish workflow to ensure you can manage this process more easily.
See also: The vMicro Menu Developing Arduino Libraries with Shared Projects