Hi,
Please try like this in your custom module:
in your py file:
from openerp.osv import fields, osv
class stock_move(osv.osv):
    _inherit = 'stock.move'
    def _get_customer_ref(self, cr, uid, ids,field_name, args, context=None):
        sale_orders = self.pool.get('sale.order')
        sale_order_line = self.pool.get('sale.order.line')
        res = {}
        for move in self.browse(cr, uid, ids, context=context):
            sale_line = sale_order_line.browse(cr,uid, move.sale_line_id.id, context=None)
            order = sale_orders.browse(cr,uid, sale_line.order_id.id, context=None)
            
            res[move.id] = order.client_order_ref
        return res
    _columns={
    
    'customer_ref':fields.function(_get_customer_ref, type="char", string="Customer Reference")
    }
in your xml file:
<openerp>
    <data>
        
           
        <record id="view_move_tree_reception_picking_inherited" model="ir.ui.view">
            <field name="name">stock.move.tree2.inherited</field>
            <field name="model">stock.move</field>
            <field name="inherit_id" ref="stock.view_move_tree_reception_picking"/>
            <field name="arch" type="xml">
                 <field name="origin"  position="after">
                    <field name="customer_ref"/>
                </field>
            </field>
        </record>  
            
    </data>
</openerp>
Hope this helps you.