Object drags wherever I touch on screen- Iphone-Unity [closed]

Question

I am trying to drag my game object using iphone touch. I am having the problem that my object is dragging wherever on the screen I touch, I want it to drag only when placing my finger on object. Here is my code:

if (Input.touchCount > 0) {                         
   Touch theTouch = Input.GetTouch (0);                                 
   Ray ray = Camera.main.ScreenPointToRay(theTouch.position);    

     if(Physics.Raycast(targetItem.transform.position, ray.direction,1.5f))             
       {                 
     if(Input.touchCount == 1) {                                                              

             float scrollDeltaX = theTouch.deltaPosition.x;
             float scrollDeltaY = theTouch.deltaPosition.y;

             scrollDistanceX = Mathf.Clamp(scrollDistanceX+scrollDeltaX*Time.deltaTime,-18,15); //limits of my screen              
             scrollDistanceY = Mathf.Clamp(scrollDistanceY+scrollDeltaY*Time.deltaTime,-10,12.5f);                              

             targetItem.transform.position = new Vector3(scrollDistanceX,scrollDistanceY,targetItem.transform.position.z);

          }                    
   }
}