Mokoko Seeds are the most abundant Lost Ark collectible, but they are hard to come by. The seeds resemble small fruits and are green in color. When found, Mokoko seeds glow. There are three Mokoko Seeds to seek out and collect on the Isle of Yearning in the Sea of Procyon. All of the seed locations are shown below.
Where to find all Mokoko Seeds on the Isle of Yearning in the Sea of Procyon
You can find the Mokoko Seed with the red circle on the east side of the island fairly easily. Take the route there as far as it takes you, and then get very close to the sea. You will walk on a path that cannot be seen from where you started until you reach the Mokoko Seed. Ignore the NPCs fighting on the other side of the fence; they may appear to be shooting at you, but they will not hurt you.
The Mokoko Seeds in the white circle are inside a cabin. Find the Mokoko Seeds by going to the location and entering the building. The image above will make finding them easier, but one is on the north side of the cabin, and the other is on the east side.
For more information on Lost Ark, check out All Mokoko Seed Rewards in Lost Ark and All World Bosses Locations in Lost Ark on Pro Game Guides.