I figured it out that if 2 pathes overlap but take opposite directions, then you may use fill atribute to color between them and avoid black out in that area.
and also if a path tag comes next, then it will cover the overlaping area.
There is a trick when u want to get the code of an svg drawing:
Draw whatever u want in "inkscape" and then open the resulting file in notepad or any similar program
And voilaa
