The record editor on the Fulcrum web app has a lot of filtering and search options. When these are used and then the download data button on the record editor is used the file that is produced will only contain the records that were returned by the filters/searches that were in use.
There are two search boxes that can be used to filter records, the global search and the column search on the table view.
To search for records that contain a similar value somewhere in the record (this includes data in child records), you can use the search bar at the top of the record editor.
To return records that have values in specific fields/columns, you can click on the header to the column and then use the search bar within pop-up that appears.
There are three filter options that you can use to filter your data, the system filter, the custom filter, and the column filter. The data that is returned by the filters will be the only data that is included in the downloaded data file.
To the left of the search box at the top of the record editor, there is a button that will open and close the filter box (open by default).
The filter options that you will find here are to only display records that were last updated within a period of time, have a certain status, assigned to specific users, and/or are tagged with a specific project tags.
To the right of the search box you will find the custom filter icon. Clicking on the custom filter icon (funnel icon) will result in the custom filters popup being displayed. Here you can create AND, OR, and NOT group filters that meet your needs.
The last filter option is the column filters. When you click on the header of a column, there is series option to filter options based on the field type that is used for that data column.