Data Graphs allows you to search within a specific Dataset or across all the Datasets in a given account, known as a "federated search".
The search box on a project home screen allows you to carry out a federated search. You do not have to specify a search term – you can perform an empty query that will return all data and allow you to navigate by facets. A free-text search can be added, as well as a filter by facet, at any stage and in any combination.
To search within a specific Dataset and use its associated facets, select the Dataset from the project home screen and search from the sidebar on the subsequent Concepts screen. You can return to a federated search at any time by navigating to the home screen.
See searching by facets for more information.