During url parsing function mb_strtolower is used to lowercase url and database data, that is matched against it. Problem is, that mb_internral_encoding('UTF-8') function is called after url parsing, when language is already available.
Because of it mb_strtolower uses default mbstring extension encoding, that in my case was "ISO-8859-1" resulting corrupted url as the result. Because of that only urls parts (between "/") in english were parsed correctly.
This way if url is "http://www.site.com/products/baskı-urünleri.html" it's only "products" part is parsed and corresponding to that section template is shown.