You're looking for a helpful guide on how to download the full web series "Kohra" from Filmyzilla or other platforms. I must remind you that downloading copyrighted content from unauthorized sources can be against the law and may harm the creators.
"Kohra" is a popular Indian web series that revolves around a murder mystery. If you're interested in watching it, I recommend exploring official channels.
That being said, I'll provide you with some general information and alternatives: