Move Camera around an object

Hello !
I am facing a problem regarding to move camera around an object with which I did perfectly… But my camera stops its rotation after rotating the given amount And I want my camera to rotate a bit after its rotation in order to give it a good look… But I m unable to do it…
Your help would be appreciated.
Thanks

    public Transform target;
public float distance = 5.0f;
public float xSpeed = 60.0f;
public float ySpeed = 60.0f;
public float yMinLimit = 10f;
public float yMaxLimit = 60f;
public float distanceMin = 5f;
public float distanceMax = 10f;
float x = 0.0f;
float y = 0.0f;

void Start()
{

			Vector3 angles = transform.eulerAngles;
			x = angles.y;
			y = angles.x;
			// Make the rigid body not change rotation
			if (rigidbody) {
		rigidbody.constraints = RigidbodyConstraints.FreezeRotationX;
		rigidbody.constraints = RigidbodyConstraints.FreezeRotationZ;

			}
	}
void Update()
{

	if (target && Input.touchCount == 1 && Input.GetTouch(0).position.x > Screen.width / 2 && Input.GetTouch(0).phase == TouchPhase.Moved) //Just orbit touch without movement
	{
		Debug.Log("Orbiting! 1 touch");
		Orbit(Input.GetTouch(0));
	}
	else if (Input.touchCount == 2)
	{
		if (Input.GetTouch(0).position.x > Screen.width / 2 && Input.GetTouch(0).phase == TouchPhase.Moved)
			Orbit(Input.GetTouch(0)); //Movement was touched second

		else if (Input.GetTouch(1).position.x > Screen.width / 2 && Input.GetTouch(1).phase == TouchPhase.Moved)
			Orbit(Input.GetTouch(1)); //Movement was touched first
	}

}

void Orbit(Touch touch)
{
	x += touch.deltaPosition.x * xSpeed * 0.1f /* * distance*/;
	y -= touch.deltaPosition.y * ySpeed * 0.1f /* * distance*/;
	y = ClampAngle(y, yMinLimit, yMaxLimit);
	Quaternion rotation = Quaternion.Euler(y, x, 0);
	//distance = Mathf.Clamp(distance - Input.GetAxis("Mouse ScrollWheel") * 5, distanceMin, distanceMax);
	RaycastHit hit;
	if (Physics.Linecast(target.position, transform.position, out hit))
	{
			//distance -= hit.distance;
	}
	Vector3 negDistance = new Vector3(0.0f, 0.0f, -distance);
	Vector3 position = rotation * negDistance + target.position;

	transform.rotation = rotation;
	transform.position = position;

	

}
public static float ClampAngle(float angle, float min, float max)
{
	if (angle < -360F)
		angle += 360F;

	if (angle > 360F)
		angle -= 360F;

	return Mathf.Clamp(angle, min, max);
}

You can just use the build in function called RotateAround :

Instead of Vector3.Zero you just put the gameobject you want to rotate around.

First of all create empty game object at Exactly where player is situated in scene .

After that set camera a little bit far from player so that camera can view player in proper view.

**Imp:**Create Main Camera as child of empty game object IE: Empty game object will parent and main camera will chield.

after that create script

void Update () { transform.Rotate(Vector3.up, Input.GetAxis("Mouse X")); }

Apply that script on Empty game object.
And run.