Try .on()
As elements are added dynamically you can not bind events directly to them .So you have to use Event Delegation.
$(document).on('keypress', '#mini_search_input', function (event) {
var keycode = (event.keyCode ? event.keyCode : event.which);
if (keycode == '13') {
alert('my event!!');
}
});
Syntax
$( elements ).on( events, selector, data, handler );