How to add a particular distance to transform.position

I would like to move the “molecule” object to UR_Detector.position += new Vector(0.4,0.4) but the syntax is not logically correct.

Any suggestion?

private void UR_Attach()
        {
            RaycastHit2D attachCheck = Physics2D.Raycast(UR_Detector.position, Vector2.one * transform.localScale, 0);
    
            if (attachCheck.collider != null && attachCheck.collider.tag == "Molecule")
            {               
                attachCheck.collider.gameObject.transform.parent = UR_Detector;
                attachCheck.collider.gameObject.transform.position = UR_Detector.position += new Vector2 (0.4,0.4);
    
                if (Input.GetKey(KeyCode.X))
                {
                    attachCheck.collider.gameObject.transform.parent = null;
                }
            }
        }

I solved by adding a new viarable to store the location of the molecule, however this is not as lean as I hoped it was