Automatically filter by Product category

Hello,

Yes, it is possible with the little code snippet. Please use code

add_filter( 'aws_search_query_array', 'my_aws_search_query_array' );
function my_aws_search_query_array( $query ) {
    if ( isset( $_REQUEST['aws_tax'] ) && $_REQUEST['aws_tax'] === 'product_cat' && isset( $_REQUEST['aws_page'] ) && $_REQUEST['aws_page'] ) {
        global $wpdb;
        $term_id = $_REQUEST['aws_page'];
        $query['search'] .= " AND ( id IN (
            SELECT object_id FROM $wpdb->term_relationships
            WHERE term_taxonomy_id IN ( select term_taxonomy_id from $wpdb->term_taxonomy WHERE term_id IN ({$term_id}))
        ) )";
    }
    return $query;
}
 
add_filter( 'aws_searchbox_markup', 'my_aws_searchbox_markup' );
function my_aws_searchbox_markup( $markup ) {
    $hidden = '<input type="hidden" name="type_aws" value="true">';
    $new_fields = '<input type="hidden" name="tax" value="'.get_query_var('taxonomy').'"><input type="hidden" name="page" value="'.get_queried_object_id().'">';
    $markup = str_replace( $hidden, $hidden . $new_fields, $markup );
    return $markup;
}

You need to add it somewhere outside the plugins folder. For example, inside functions.php file of your theme or use some plugin for adding code snippets.

Also after adding this code you will need to go to the plugin settings page and click the ‘Clear cache’ button.

Regards

Please modify your code a bit. Use instead

add_filter('yith_ywraq_quantity_loop','__return_true');

add_action( 'woocommerce_archive_description', 'my_woocommerce_before_shop_loop' );
function my_woocommerce_before_shop_loop() {
    if ( is_tax( 'product_cat' ) && function_exists( 'aws_get_search_form' ) ) {
        aws_get_search_form( true );
    }
}

add_filter( 'aws_search_query_array', 'my_aws_search_query_array' );
function my_aws_search_query_array( $query ) {
    if ( isset( $_REQUEST['aws_tax'] ) && $_REQUEST['aws_tax'] === 'product_cat' && isset( $_REQUEST['page'] ) && $_REQUEST['page'] ) {
        global $wpdb;
        $term_id = $_REQUEST['page'];
        $query['search'] .= " AND ( id IN (
            SELECT object_id FROM $wpdb->term_relationships
            WHERE term_taxonomy_id IN ( select term_taxonomy_id from $wpdb->term_taxonomy WHERE term_id IN ({$term_id}))
        ) )";
    }
    return $query;
}
 
add_filter( 'aws_searchbox_markup', 'my_aws_searchbox_markup' );
function my_aws_searchbox_markup( $markup ) {
    $hidden = '<input type="hidden" name="type_aws" value="true">';
    $new_fields = '<input type="hidden" name="aws_tax" value="'.get_query_var('taxonomy').'"><input type="hidden" name="page" value="'.get_queried_object_id().'">';
    $markup = str_replace( $hidden, $hidden . $new_fields, $markup );
    return $markup;
}

Please try to update your code with following one

add_filter('yith_ywraq_quantity_loop','__return_true');

add_action( 'woocommerce_archive_description', 'my_woocommerce_before_shop_loop' );
function my_woocommerce_before_shop_loop() {
    if ( is_tax( 'product_cat' ) && function_exists( 'aws_get_search_form' ) ) {
        aws_get_search_form( true );
    }
}

add_filter( 'aws_search_query_array', 'my_aws_search_query_array' );
function my_aws_search_query_array( $query ) {
    if ( isset( $_REQUEST['aws_tax'] ) && $_REQUEST['aws_tax'] === 'product_cat' && isset( $_REQUEST['page'] ) && $_REQUEST['page'] ) {
        global $wpdb;
        $term_id = $_REQUEST['page'];
        $term_in = array();

        $term_childrens = get_term_children( $term_id, 'product_cat' );
        if ( ! is_wp_error( $term_childrens ) && $term_childrens ) {
            foreach( $term_childrens as $term_children ) {
                $term_in[] = $term_children;
            }
        }

        $term_in[] = $term_id;

        $query['search'] .= " AND ( id IN (
            SELECT object_id FROM $wpdb->term_relationships
            WHERE term_taxonomy_id IN ( select term_taxonomy_id from $wpdb->term_taxonomy WHERE term_id IN (" . implode( ',', $term_in ) . "))
        ) )";
    }
    return $query;
}

add_filter( 'aws_searchbox_markup', 'my_aws_searchbox_markup' );
function my_aws_searchbox_markup( $markup ) {
    $hidden = '<input type="hidden" name="type_aws" value="true">';
    $new_fields = '<input type="hidden" name="aws_tax" value="'.get_query_var('taxonomy').'"><input type="hidden" name="page" value="'.get_queried_object_id().'">';
    $markup = str_replace( $hidden, $hidden . $new_fields, $markup );
    return $markup;
}