Good with essentials? Then please help me!

Hey guys,

I am co-owner on a pixelmon adventure server, and I want to disable picking up several items. I know there is a way to do this for selected items, but I am not 100% sure how to, I've tried to do this several times, but it did not just work. Please reply to this post if you can help me or have any idea on how to do this

Some of the plugins we have, that might help you help us out:
Essentials
World Edit
Essentials Anti Build
Essentials Chat
Essentials Kit Edit
Vault
Enjin Minecraft Plugin
World Guard
Essentials Spawn
Essentials Protect
Group Manager

Please help me if you have a on how to help us out!