In some languages which use extensively UTF8 encoding for extra chars, results of the search give lines that are abusively double encoded in UTF8, resulting in bad display of those titles.

This is resolved in using the xxxxxxxx_link_post_processing($title) callback in each document so title can be backcoded properly to UTF8 by :

mb_convert_encoding($title, 'UTF-8', 'auto');

(as a default processing).