Adding hooks to theme

In one of the previous support topics, I came across the following advice:

make sure that your theme has the following woocommerce’s hooks

woocommerce_before_main_content

woocommerce_before_single_product_summary
woocommerce_single_product_summary
woocommerce_after_single_product_summary

you can also try to add this to the functions.php file of your theme

if ( function_exists( ‘YITH_WPC’ ) ) {

add_action( ‘woocommerce_before_single_product’, array( YITH_WPC(), ‘check_show_ywpc_product’ ), 5 );

}

So my question is, how would I go about adding or ensuring that my theme already has these hooks?

The reason I ask is because, no matter what I do, I can only get the timer to show if I use the shortcode, and then it’s only shown in the description (vs. above the title, for example).

I already did the second part (adding the function to functions.php), but that doesn’t seem to have helped.

Thank you!