User-agent: Yandex
Disallow: /preview/*
Disallow: /_sys-dynamic
Disallow: /-/
Disallow: *?
Clean-param: nw&id&from&text

User-agent: Googlebot
Disallow: /preview/*
Disallow: /_sys-dynamic
Disallow: /-/
Disallow: *?

User-agent: *
Disallow: /preview/*
Disallow: /_sys-dynamic
Disallow: /-/
Disallow: *?