[Recipe: Major Rejuvenation Potion] is not completing (allready learned it and have a spare in my bag + crafted [Major Rejuvenation Potion] as it said in F.A.Q) is says it dropes from all the bosses in MC

The crafted item is a different category and is only for transmog gear. What you are wanting is the recipe tracking itself.

Make sure you are on Version 1.6.5a
Next you will want to go to Settings and choose the first tab
Scroll to the bottom and choose "Show Profession Mini List"
Next open up your profession window and this allows Blizzard to send the information to ATT and let's it cache the information.
After that you should have it marked collected. If not do a Shift+Click on the header.