Answers for "boostrap 4 search button"

bootstrap 4 search bar

<form class="form-inline">
  <input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
  <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
</form>

Bootstrap 4 Search Box

<div class="input-group mb-3">
  <input type="text" class="form-control" placeholder="Search" aria-label="Search" aria-describedby="basic-addon2">
  <div class="input-group-append">
    <span class="input-group-text" id="basic-addon2">Search/span>
  </div>
</div>