I have added that code just like example to point you to the right direction that you need to use custom code to style the widget according to your needs. You need to edit the styles depending on the result you want to achieve. I’m sorry but additional customization is outside the scope of our support https://themeforest.net/page/item_support_policy
Contact Yith search plugin author if you need help with styles of their search form.
One standard license is valid only for 1 project. Running multiple projects on a single license is a copyright violation.