You can use conditional is_page to define different menu items as you want.
if ( is_page( 'About' ) ) {
wp_nav_menu( array( 'container' => false, 'menu_id' => 'menu-left-side-menu', 'menu_class' => 'menu', 'theme_location' => 'about-page' ) );
} elseif ( is_page( 'Services' ) ) {
wp_nav_menu( array( 'container' => false, 'menu_id' => 'menu-left-side-menu', 'menu_class' => 'menu', 'theme_location' => 'services-page' ) );
} elseif ( is_page( 'Contact' ) ) {
wp_nav_menu( array( 'container' => false, 'menu_id' => 'menu-left-side-menu', 'menu_class' => 'menu', 'theme_location' => 'contact-page' ) );
} else {
wp_nav_menu( array( 'container' => false, 'menu_id' => 'menu-left-side-menu', 'menu_class' => 'menu', 'theme_location' => 'default-menu' ) );
}
And you can define as many menu as you want in your theme.
register_nav_menus(
array(
'about-page' => __( 'About Page Menu' ),
'services-page' => __( 'Services Page Menu' ),
'contact-page' => __( 'Contact Page Menu' ),
'default-page' => __( 'Default Page Menu' ),
'left' => __( 'Left Menu' )
)
);
If you don’t want to use many menus then you can simply add all items in one single menu and hide non-required menu items on each page with the help of WordPress body classes and CSS styles.