No offense, but there’s a Tip written in the Day’s End screen that says “Tip: You can right-click on potions and items to get descriptions!” I kind of don’t know what more to do.
I know there is. I do feel stupid for forgetting but when its this easy to forget I'm leaning towards the game needing a little something.
Perhaps when a player mouses over an icon for a few seconds a little text box can appear under the cursor, gently reminding them about right clicking. Or perhaps right clicking should be a toggle, not a hold option to help cement it's existence into players minds. Finally you could darken the rest of the screen while a tooltip it on screen. Since this transforms the tooltip into a screenwide effect it'll be more memorable.