Sorry guys that I did not report back here earlier in this topic.
On Tuesday 10 Feb. my friend in Sofia
got the package.

All went as described here in this topic from the post office near the customs, she needed the CL number provided from the (german)DHL tracking site.
No idea why this went so fast and others so slow, one thing is sure that this package went to Frankfurt first and there is a DHL distribution center located with airfield so I suspect that this went by air.
Wednesday 4 feb. send from store germany with DHL.
Friday 6 Feb. Outside Germany untracked.
Tuesday 10 Feb. Got the package.
Maybe it was Monday 9 Feb. already in Sofia we don`t know, did not made a pick-up attempt.
I have used DHL a few times to send goods or documents from here to abroad and that was with the express service it is fast and has a good tracking system only not usable for hobby goods therefore it is too expensive.
Misho about the premium service I did not knew that, will keep that one in mind and also the price is reasonable.
Online shop Lippe sends all packages for 9 euro with this DHL/(Now I know)Bulpost(or for other countries other local post companies) construction. Lippe must have a good deal/contract with DHL/Deutschepost in this case that they can send for this price.
Not sure if this is the right conclusion but maybe the difference in how the packages travel begin with how the sender send the package since there seems a lot of different ways to send a package.
But after all it is good to have it all in one topic now, not only to share experiences about this subject but also for our other fellow model train colleagues so they can see what possibilities there are or where the problems may have occurred.
My next package I hope will be locally but that depends on Vlado.

Thanks all for the great tips and help!!