Woocommerce seriously overuses this hooks feature, making the code much much harder to follow.
I suggest a decent IDE with full project search features.
Back to your specific problem, provided this is a one off site (not a theme to be sold) then just dive straight into the template files themselves.
Copy the woocomerce folder to your theme (already done i believe) then edit yourthemefolder/woocommerce/content-single-product.php