Is there a way to browse all of the layers in another organization? For example, I might want to search through all of the content on my states highway department. I know we can search for content but I presume that many organizations will tag data with highway, my state, etc which may produce extra results in the search that I do not need.
If the other organization's ArcGIS Online home page is accessible (i.e. https://otherorg.maps.arcgis.com), you can click on the gallery tab to view their content specifically. Otherwise when you perform a search, yes it will search the entirety of ArcGIS Online.