:GetPartsInPart loop only finding 1 part when multiple are present

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#1

Hello, I am trying to make a weapons system–mainly projectiles with piercing and more aspects, but the piercing does not work. After finding one part, the whole loop proceeds to not find any more.

local checkForParts = coroutine.create(function(part, currType)  
while part ~= nil do
	wait()
	local gotten = game.Workspace:GetPartsInPart(part, filter)

	for _, thing in pairs(gotten) do
		if thing.Parent:FindFirstChild("Humanoid") and hitDb[thing.Parent] == nil then
			hitDb[thing.Parent] = true
			if currType == "Normal" and script.CurrentWeapon.Value == "Slingshot" or piercingEnabled == true and script.CurrentWeapon.Value == "Slingshot" then
				game.ReplicatedStorage:WaitForChild("TakeDmg"):FireServer(thing.Parent.Humanoid, 10)
			elseif currType == "Poison" and script.CurrentWeapon.Value == "Slingshot" then
				coroutine.resume(tickDmgFunc, thing.Parent.Humanoid, slingAddons[1][3], 7)
			elseif currType == "Burn" and script.CurrentWeapon.Value == "Slingshot" then
				coroutine.resume(tickDmgFunc, thing.Parent.Humanoid, slingAddons[2][3], 10)
			end

			if currType == "Normal" and script.CurrentWeapon.Value == "Sword" then
				if swordCombo == 1 then
					game.ReplicatedStorage:WaitForChild("TakeDmg"):FireServer(thing.Parent.Humanoid, 10)
				elseif swordCombo == 2 then
					game.ReplicatedStorage:WaitForChild("TakeDmg"):FireServer(thing.Parent.Humanoid, 15)
				end
			end

			local co

			if script.CurrentWeapon.Value == "Slingshot" then
				co = coroutine.create(function()
					task.wait(0.5)
					hitDb[thing.Parent] = nil
				end)
			elseif script.CurrentWeapon.Value == "Sword" then
				co = coroutine.create(function()
					task.wait(0.6)
					hitDb[thing.Parent] = nil
				end)
			end

			coroutine.resume(co)
				if piercingEnabled == true then
					if pierceAmt < slingAddons[3][3] then
						pierceAmt += 1

						individualThingy[part.Name] = thing
					elseif pierceAmt >= slingAddons[3][3] then
						individualThingy[part.Name] = thing

					       return
					end
				elseif currType ~= "Piercing" then
					individualThingy[part.Name] = thing

					return
				end
				print(part.Name, individualThingy[part.Name])

				return
			elseif not thing.Parent:FindFirstChild("Humanoid")  then
				if piercingEnabled == true  then
					if pierceAmt < slingAddons[3][3] then
						pierceAmt += 1

						individualThingy[part.Name] = thing
				        elseif pierceAmt >= slingAddons[3][3] then
						individualThingy[part.Name] = thing

						return
					end
				elseif currType ~= "Piercing" then
					individualThingy[part.Name] = thing

					return
				end
			end
		end
	end
end)

(sorry for the messy code, and the bad formatting)