User-agent: *
Disallow: /pdf/

User-agent: Yandex
Disallow: /pdf/

User-agent: Yandex 
Disallow: /amc/instr/instr.html 

User-agent: Yandex 
Disallow: /amc_report.html 

User-agent: Yandex 
Disallow: /serdi_instruction.html

User-agent: Yandex 
Disallow: /serdi/instr/instr.html