Multiples functions on customize_register?

For a better organization of my theme’s functions.php, i would like to know if it’s possible to add multiples functions with add_action on customize_register ?
Like this for exemple :

function banana_customize($wp_customize) {
///// Content of function }
add_action('customize_register','banana_customize')

function coconut_customize($wp_customize) {
///// Content of function }
add_action('customize_register','coconut_customize')

If i do this, i have an error and page won’t load.

If this is not possible, could you tell me how to combine functions like so :

function banana_customize($wp_customize) {
///// Content of function }

function coconut_customize($wp_customize) {
///// Content of function }

" function combined_functions = banana_customize + coconut_customize "

add_action('customize_register','combined_functions')

Thanks in advance 🙂