Hi,
There is nothing to do in HikaMarket and I can't modify anything in HikaMarket in order to provide that feature.
It is related to the HikaShop filter system which need to be improved to let add-ons have interaction with it.
Otherwise, you can create a filter on the field "product_vendor_id" and provide the list of the available values ; but it won't be something dynamic.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.