To customize the fields that are exported when you Export CSV (or Export XML) for an Item, there are 3 field sets for each export feature (either Export or Export XML). The field sets are exported in this order: Assembly, Item Revision, then Manufacturer Item.
1. Go to SalesForce Classic
2. Go to Setup
3. Search for Objects
4. Select Item Revisions or any other object (Assembly and Manufacturer Item)
5. Got to Field Sets and select Edit
6. Add to any relevant Field Set:
- Export: sets fields in export file in the format of CSV
- Export XML: sets fields in export file in the format of XML
Note: Rich text works fine in both CSV and XML Export
Note: Cost columns are included in exports by default. To exclude a cost, go to Setup -> Custom Settings and click the Manage link for Item Cost Mapping. You can edit the cost type to exclude and click Hide from Export.