After defeating Kahuna Hala, you can break open the path to Ten Carat Hill and meet new pokémon.
Open Ten Carat Hill
Go upward from the entrance to find an X Attack.
Go downward from there and use Tauros to break through the rocks. Get off of Tauros and go through the narrow path up above to find a Super Potion. Keep going leftward along this ledge to find an Ultra Ball.
Jump down from the ledge, and use Tauros to go to the left through the rocks. Eventually, there will be a large block to the left that you can't break. Ignore that for now. When you are able to push the rock aside later, read the Beyond the Rock section below.
Go upward and you reach Farthest Hollow.
Farthest Hollow
Go upward and there is a Hard Stone partially hidden behind the grass to the left. Go farther upward and you find a Nugget. Go left and down from there, and go through the grass to find a Great Ball. Then go back through the grass, and go to the right and up from there to find a Burn Heal.
From there, go down and left to enter some grass. Go through the grass to reach a slope. Go up the slope to find TM62 Acrobatics.
That is all that there is to be found in Ten Carat Hill, so you can either use an Escape Rope to go back to Route 1 Hau'oli Outskirts, or you can go back down the slope, back through the grass, and go left and down to exit the area.
After this, you should go to Hau'oli City Marina.
Beyond the Rock
Read this section after you are able to push aside the big rock that you found inside Ten Carat Hill earlier.
Go to the left from the rock. Before going outside, check on the rock to the left to find a hidden Protein.
Then go outside to get Flyinium Z.