Docusign Insight - How to search for documents based on Import date?

Open the ScD UI and go the the 'Contracts' tab. Within the search query start your search by using the query "ImportedAt:", see below example:
 

ImportedAt:[2018-01-14T00:00:00Z TO *]

The above example will return all Documents that have been successfully imported since Jan 14th 2018 until present. The "*" character is a wildcard essentially stating any result is acceptable and thus no 'To' date is set in the above example.

If you want to specify a specific date range, consider using a query as follows:
ImportedAt:[2018-01-14T00:00:00Z TO 2018-01-20T00:00:00Z]

With the changes in the above example, only Documents imported from Jan 14th 2018 until the 20th of the same month and year will be returned.