Bill Anton has a method for understanding large tabular models on legacy platforms:
Unfortunately, the Tabular Model Explorer is only available for 2016 (compatibility 1200) tabular models – which many folks haven’t moved over to just yet (despite the overwhelming list of reasons why SQL 2016 is one of the best releases in a very long time).
Those of us stuck with 2012/2014 environments have no other option than to comb through the diagram view for that one table we’re looking for…or scan the unordered list of tables/columns in grid view, or arrow-key through a bunch of cells in the calculation pain pane to find a particular measure… or so I thought up until a few weeks ago when I discovered a better way!
At least 60-70% of the DBA population would chafe at the idea that is a “legacy” platform, so maybe I’m overstepping it a little with calling 2014 legacy. But seriously, 2016 is a huge improvement, well worth the jump.