WordPress at a glance
action is not described

woocommerce_settings_save_(current_tab) action-hook . WC 1.0

Trigger actions.

Usage

add_action( 'woocommerce_settings_save_(current_tab)', 'action_function_name_9334' );
function action_function_name_9334(){
	// action...
}

Where the hook is called

WC_Admin_Settings::save()
woocommerce_settings_save_(current_tab)
woocommerce/includes/admin/class-wc-admin-settings.php 77
do_action( 'woocommerce_settings_save_' . $current_tab );

Where in WP core the hook is used WooCommerce

woocommerce/includes/admin/settings/class-wc-settings-page.php 43
add_action( 'woocommerce_settings_save_' . $this->id, array( $this, 'save' ) );
woocommerce/includes/admin/settings/class-wc-settings-tax.php 36
add_action( 'woocommerce_settings_save_' . $this->id, array( $this, 'save' ) );