I also tried this as I assumed it was searching all symbols, but it looks like it's only searching artifacts. Once you're into an artifact you get a search within that.
The keyboard navigation on the search doesn't work (pressing enter closes the results, doesn't navigate), and I find a search over artifacts to be too limiting for my use-case, but I guess it's not wrong.
I think I was extra confused because the HN title says it searches "packages" so I assumed that was what it was doing (in a java sense, where a package is the classes inside a library).
The keyboard navigation on the search doesn't work (pressing enter closes the results, doesn't navigate), and I find a search over artifacts to be too limiting for my use-case, but I guess it's not wrong.