How to handle overlapping in a random position spawning script?

I have a script that spawns enemies in random positions. But they occasionally spawn inside other objects or on top of other enemies. How do I handle this problem?

local enemies = game:GetService("ReplicatedStorage").NPC.Enemies
local clonePlace = workspace.NPC.Enemies
local enemycount = script.Parent.EnemyCount
local enemytype = script.Parent.EnemyType
local maxnumber = script.Parent.MaxNumber
local delaytime = script.Parent.Delay
local increment = script.Parent.Increment

local spawner = script.Parent


while wait(delaytime.Value) do
    if enemycount.Value < maxnumber.Value then
        enemycount.Value = enemycount.Value + 1

        local clonedEnemy = enemies:FindFirstChild(enemytype.Value):Clone()
        clonedEnemy.Parent = clonePlace

        local minX = spawner.Position.X - increment.Value
        local maxX = spawner.Position.X + increment.Value

        local minZ = spawner.Position.Z - increment.Value
        local maxZ = spawner.Position.Z + increment.Value

        clonedEnemy.Head.CFrame = CFrame.new( math.random(minX, maxX), spawner.Position.Y + 15, math.random(minZ, maxZ) )
    end
end