what are the dwarfs of blue mountains?

I would add to what eldariontkd wrote to say that Appendix A to LotR tells us that some Dwarves remained in the Blue Mountains throughout the Second and Third Ages, especially in the southern range where they still had active mines. There were also the Longbeards who set up shop in the Blue Mountains (probably north of the Grey Havens) after the War of the Dwarves and Orcs, but many (if not all) of them would have returned to Erebor after the Battle of Five Armies.

The Broadbeams and Firebeards built the cities of Belegost and Nogrod in the First Age. Those cities were destroyed in the War of Wrath, and the dwarves migrated to Khazad-dum, where the Longbeards (Durin's Folk) lived.

In the Third Age, the Longbeards settled in the Blue Mountains for a short time after being driven out of the Lonely Mountain by Smaug.