You should be able to solve this problem by defining one or more custom fields to store the required information (e.g., Identity Document Number). Bitwarden will also auto-fill this information if you set the Name of the custom field to match the identifier of the input field on the login form. To find the correct name to use for the custom field, please read the relevant Help Center article.
In addition, a demonstration of the custom field technique is available in this blog post: