How do I get the Alias Path/Node Alias in C# Kentico 12 MVC

I am using the standard DocumentHelper.GetDocuments to find a page, and for top level pages, the .WhereEquals("NodeAlias", pageAlias) is working fine, where pageAlias is along the lines of "Test-Page".Once I start resolving child pages (so pageAlias = "Test-Page/Another-Page") DocumentHelper is returning null. I am wondering if I can see the NodeAlias for the pages in C# somehow? This should allow me to map the pages better.