How to use Or condition for two different field in custom filter ?

As per documentation for endpoint filterList, a structure like that should work:

$viewdefs['Accounts']['base']['filter']['basic']['filters'][] = array(
	'id' => 'filterRQPartners',
	'name' => 'LBL_FILTERRQPARTNERS',
	'filter_definition' => array(
		array(
			'$or' => array(
				'ignore_dealer_in_report_c' => array(
					'$equals' => 0
				),
				'dead_2_c' => array(
					'$equals' => 0
				),
			),
		),
	),
	'editable' => false,
	'is_template' => true,
);

Regards

I have already tried this but it's not working  for two different fields. 

did you try on JS side ?

Yes, I tried in relate.js 

The example André gave is accurate. 

Can you elaborate on what you mean by the filter not working? What exactly is not working? Is it not showing up in the list of filters? Is the criteria not being respected? Please share as much detail as possible and code snippets where appropriate.

Also, I am a bit confused as to what you are trying to do as filters should be defined in PHP, per André's example, but you are indicating you did something in relate.js. 

Please clarify.

Let me explain the scanario in more details. As per below screenshot , I want to use these 2 filter  auto select on one of the dropdown selection , As per sugar default flow ,  For these 2 fields , 'AND' expression is being used , but i have to use 'OR' expression . 

Below are the code , i used for this : 

File : relate.js 

selectLocation: function () {
    var m03_work_product_name = this.model.get('m03_work_product_ii_inventory_item_1_name');
    console.log('m03_work_product_name', m03_work_product_name);
    var filterOptions = new app.utils.FilterOptions()
            .config({
                'initial_filter': 'FilterTestSystem',
                'initial_filter_label': 'Current Work Product Assignment',
                
                'filter_populate': {
                    'assigned_to_wp_c': m03_work_product_name,
                    'm03_work_product_id_c': ['4a529aae-5165-3149-6db7-5702c7b98a5e']
                },
                'filter_relate': {
                    'assigned_to_wp_c': m03_work_product_name,'m03_work_product_id_c': ['4a529aae-5165-3149-6db7-5702c7b98a5e'],
                },
            })
            .populateRelate(this.model)
            .format();
    //this custom code will effect for all relate fields in Enrollment module.But we need initial filter only for Test system relate field.
    filterOptions = (this.getSearchModule() == "ANML_Animals") ? filterOptions : this.getFilterOptions();
    app.drawer.open({
        layout: 'selection-list',
        context: {
            module: this.getSearchModule(),
            fields: this.getSearchFields(),
            filterOptions: filterOptions,
        }
    }, _.bind(this.setValue, this));
},

file : Filtertest.php : 

$viewdefs['ANML_Animals']['base']['filter']['basic']['filters'][] = array (
  'id' => 'FilterTestSystem',
  'name' => 'Current Work Product Assignment',
 
'filter_definition' => array(
  array(
    '$or' => array(
      'assigned_to_wp_c' => array(
        '$equals' => ''
      ),
      'm03_work_product_id_c' => array(
        '$in' => ''
      ),
    ),
  ),
),

  'editable' => true,
  'is_template' => true,
);

By using this ,  no filter is working , Please check and suggest me any solution.

@André Lopes Would you please suggest me any way  ?