In order to override any template file, first you need to create a child theme and then you have to create a folder called “dc-product-vendor” and copy the template file inside that (i.e. the file path would be yourtheme/dc-product-vendor/template_file_name.php) and modify this as per your requirement.
Let us know if you have any further query.
p.s. The response might get delayed as our office is closed due to Holidays and we will reopen on 2nd January 2018.