Bulgaria and Macedonia public transit - Kosovo

Hi everyone ,

Recommendations on where I can book and search for public transit between Sofia, Plodiv, Velika Tarnovo, and Skopje?

Also, according to google maps Poldiv to Velika Tarnivo is apex 14 hrs. By public transit. Would it be smarter to hire a private driver ?

And is there a good day trip tour from Skopje to Kosovo?

We are planning on going for march break.

Thanks Amy