You can search for documents from 2 places
1. From the dashboard you have a search field in the top left corner, here you can search for exactly the document name, part of the name or document ID. Insert the search criteria and press enter.
You will now see a list of documents with the word Test in the title
You can also set a filter to not search in all documents by clicking the filter button and make the filter choice and press OK button before searching
2. In report index you also have a search field to search for the same, and from reportindex search it will also search inside document content and will most probably give you a different output than search on dashboard.