Hi,
It's not a Joomla module which can be downloaded, it's a module present by default in HikaShop.
So you can re-configure it if you no more have it, you can see the configuration on our demo website.
If it only shows one category, it means that there is only one category configured under the "product categories" category in your HikaShop backend, or that you changed the "parent category" option of the module to something else than "product categories", or that the "Only display categories with products" option of the module is turned on and that the other categories don't have any product in them.