See section 3 of this wiki
http://kodi.wiki/view/Log_file/Advanced
You can also learn how to create debugging logs.
Log files are lengthy and somewhat impenetrable. Look for lines starting with the words "error".
It is always worth checking twitter, facebook or developer forums to see if an addon is experiencing current problems (you should do this with robocop) to avoid wasting your time and energy.
The tvaddon developers and other developers welcome debugging logs from users for the addons they support. Learn how to create them (tvaddons has guides) and help the kodi addon community.