diff --git a/locale/es.po b/locale/es.po
index e560736..62b6fca 100644
--- a/locale/es.po
+++ b/locale/es.po
@@ -132,4 +132,8 @@ msgstr "ul_quantity"
 
 msgctxt "view:sale.cost.template:"
 msgid "ULs quantity:"
-msgstr "UdCs:"
\ No newline at end of file
+msgstr "UdCs:"
+
+msgctxt "model:ir.action,name:act_relate_sale_unit_load"
+msgid "Unit loads"
+msgstr "Unidades de carga"
\ No newline at end of file
diff --git a/tryton.cfg b/tryton.cfg
index b9b61c2..66f6dfa 100644
--- a/tryton.cfg
+++ b/tryton.cfg
@@ -13,3 +13,4 @@ extras_depend:
 xml:
   sale.xml
   sale_reporting.xml
+  unit_load.xml
diff --git a/unit_load.py b/unit_load.py
index 8f59029..c109095 100644
--- a/unit_load.py
+++ b/unit_load.py
@@ -11,9 +11,11 @@ class UnitLoad(metaclass=PoolMeta):
 
     customer = fields.Function(fields.Many2One('party.party', 'Customer'),
         'get_customer')
-    sale = fields.Function(fields.Many2One('sale.sale', 'Sale'), 'get_sale')
+    sale = fields.Function(fields.Many2One('sale.sale', 'Sale'), 'get_sale',
+        searcher='search_sale')
     sale_line = fields.Function(
-        fields.Many2One('sale.line', 'Sale line'), 'get_sale_line')
+        fields.Many2One('sale.line', 'Sale line'), 'get_sale_line',
+        searcher='search_sale_line')
 
     def get_customer(self, name=None):
         return self.shipment_out.customer.id if self.shipment_out else None
@@ -28,3 +30,26 @@ class UnitLoad(metaclass=PoolMeta):
             if m.origin and m.origin.__name__ == 'sale.line' and
             m.state not in ('draft', 'cancel')]
         return moves[0].origin.id if moves else None
+
+    @classmethod
+    def search_sale_line(cls, name, clause):
+        _field = 'moves.origin'
+        if '.' in clause[0]:
+            _field += '.%s' % clause[0][10:]
+        else:
+            if isinstance(clause[2], (int, list, tuple, set)):
+                _field += '.id'
+            else:
+                _field += '.rec_name'
+
+        return [(_field,) + tuple(clause[1:]) + ('sale.line',)]
+
+    @classmethod
+    def search_sale(cls, name, clause):
+        _field = 'sale_line.%s' % clause[0]
+
+        if isinstance(clause[2], (int, list, tuple, set)):
+            _field += '.id'
+        else:
+            _field += '.rec_name'
+        return [(_field, ) + tuple(clause[1:])]
diff --git a/unit_load.xml b/unit_load.xml
new file mode 100644
index 0000000..e9688a0
--- /dev/null
+++ b/unit_load.xml
@@ -0,0 +1,18 @@
+<?xml version="1.0"?>
+<!-- The COPYRIGHT file at the top level of this repository contains the full
+     copyright notices and license terms. -->
+<tryton>
+    <data>
+        <!-- form relate -->
+        <record model="ir.action.act_window" id="act_relate_sale_unit_load">
+            <field name="name">Unit loads</field>
+            <field name="res_model">stock.unit_load</field>
+            <field name="domain" eval="[('sale', 'in', Eval('active_ids'))]" pyson="1"/>
+        </record>
+        <record model="ir.action.keyword" id="act_relate_sale_unit_load_keyword">
+            <field name="keyword">form_relate</field>
+            <field name="model">sale.sale,-1</field>
+            <field name="action" ref="act_relate_sale_unit_load"/>
+        </record>
+    </data>
+</tryton>
\ No newline at end of file