Bus from Dzerjinsk to Kostroma

Hello.
I’m travellling to Russia next month and i’m trying to organize the trip. So far it has been mostly easy as the cities i pretend to visit are connected by train. But there is a situation I don’t seem to be able to solve:
I plan to travel from Dzerjinsk (from Nijni Novgorod) to Kostroma. I know the cities are connected by train but it takes about 11 hours or so. Seeing in the map there is at least a road connected them and it would take about 5.30 hours by car to connect them.
My question is: are there any buses that can make the trip? I already tried looking but I don’t be able to find any.
Thank you so much.

According to Yandex Maps there is a direct bus but takes 8 hours

https://yandex.com/maps/?ll=42.466348%2C57.050554&mode=routes&routes[timeDependent][time]=2024-03-28T07%3A00%3A00&routes[timeDependent][type]=departure&rtd=0&rtext=56.326797%2C44.006516~57.767918%2C40.926894&rtt=mt&ruri=ymapsbm1%3A%2F%2Fgeo%3Fdata%3DCgg1MzEwNTA3OBIr0KDQvtGB0YHQuNGPLCDQndC40LbQvdC40Lkg0J3QvtCy0LPQvtGA0L7QtCIKDa0GMEIVpE5hQg%2C%2C~ymapsbm1%3A%2F%2Fgeo%3Fdata%3DCgg1MzA1Njk0MRIe0KDQvtGB0YHQuNGPLCDQmtC-0YHRgtGA0L7QvNCwIgoNJLUjQhVZEmdC&z=8.81

A direct taxi around 5 hours and 15.441 rubles:
https://yandex.com/maps/?ll=42.455161%2C57.050818&mode=routes&rtext=56.326797%2C44.006516~57.767918%2C40.926894&rtt=taxi&ruri=ymapsbm1%3A%2F%2Fgeo%3Fdata%3DCgg1MzEwNTA3OBIr0KDQvtGB0YHQuNGPLCDQndC40LbQvdC40Lkg0J3QvtCy0LPQvtGA0L7QtCIKDa0GMEIVpE5hQg%2C%2C~ymapsbm1%3A%2F%2Fgeo%3Fdata%3DCgg1MzA1Njk0MRIe0KDQvtGB0YHQuNGPLCDQmtC-0YHRgtGA0L7QvNCwIgoNJLUjQhVZEmdC&z=8.81