drop rates

I'm on my 80th run of underbog for my second Hatebringer listed as a 12% drop on wowhead. https://www.wowhead.com/item=24461/hatebringer I saw one on my 17th attempt, but after another 50+ attempts, I have not seen a single one drop. I've gotten the belt that's listed as a 1.7% drop on wow head...

Hello, I really hope this is not a duplicate thread, but I have a few questions regarding some of the items from the Outland dungeons: 1. https://www.wowhead.com/item=23887/schematic-rocket-boots-xtreme from the Steamvault, what is the real drop chance, I know they only drop if you have Outland...