Naruto Shippuden: Ultimate Ninja Storm 2

This should come naturally over time as you play, so long as you interact with everything you see when walking to/from everywhere to progress the story. Most plants, mushrooms, leaf piles, and vases can be interacted with and will contain an item, and there are many animals (frogs, birds, bunnies, etc.) that will drop an item when scared by you running into them. You can increase the amount of items you find for a little bit by praying at a shrine which will make you feel luckier. After your 500th item the achievement should pop.