User-agent: Yandex bot
Disallow: /

User-agent: yandex
Disallow: /

User-agent: MJ12bot
Disallow: /

User-agent: * 
Disallow: /administrator/
Disallow: /cache/
Disallow: /components/
Disallow: /editor/
Disallow: /help/
Disallow: /images/
Disallow: /includes/
Disallow: /language/
Disallow: /mambots/
Disallow: /media/
Disallow: /modules/
Disallow: /templates/
Disallow: /installation/
Disallow: /component/option,com_events/
Disallow: /new/
Disallow: /js/