Blocksy Free Theme Header Customization

Hello. I am trying using the header builder that comes with blocksy theme. I need the html element but I have already used and I need another one. Since it needs the pro version, I decided to add the search element and replace the search element code with my own. The header builder codes are inside the inc folder. However, upon copying it to the child theme and adding my code, the changes didn't work. It only when works when I directly edit the parent theme. How can I make the changes get displayed from the child theme?