I am just explored jessyink & create my first presentation.

I have some question :
Let say I have 15 layers as 15 slides. How to jump to specific layers/slides. something like if I want jump to slide number 14 and back to number 5 & move again to number8 etc ? ( I mean in browser )

What exactly do you mean with "browser"? If it is something within Inkscape, you could use the Layers menu (Shift +Ctrl + L), right click on the layer you'd like to display, and choose "Show/hide other layers".

Otherwise, if you're talking about Inkview, I don't think it's possible to jump to other slides, other than the previous, next, first and last slides.

[Edit] Oh wait, it's with JessyInk. Got not much experience with it, will take a better look later today!

Just press "i" on the keyboard to see an overview of slides in your browser. Click on any of the slides to jump to it.