Adicione Javascript KeyUp na entrada
<input type="text" class="form-control" placeholder="Search" id="search_id"/>
<script type="text/javascript">
const log = document.getElementById('search_id');
document.addEventListener('keyup', logKey);
function logKey(e) {
const value=log.value;
if (e.key === 'Enter' || e.keyCode === 13) {
transmit({search: value});
}
};
</script>
Harveyhase68