JEI's search box can be seen from (almost) any GUI in the bottom right of the screen. JEI has a lot of addons, generally adding extra modded recipe support like Thaumic JEI. This list is useful for checking recipes and uses for items, and can also be used to search for items in opened GUIs. This list can be searched via a text box at the bottom.
Based off of NEI, JEI modifies the existing Inventory GUI by adding an icon list of items to the far right. JEI, or Just Enough Items, is a utility mod made by mezz.
