bootstrap 4 search bar

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

1<div class="input-group">
2	<input id="search-input" type="search" class="form-control" placeholder="Search anything...">  
3  	<button id="search-button" type="button" class="btn btn-primary">
4    <i class="fa fa-search"></i>
5  	</button>
6</div>

1<div class="input-group">
2  <div class="form-outline">
3    <input id="search-input" type="search" id="form1" class="form-control" />
4    <label class="form-label" for="form1">Search</label>
5  </div>
6  <button id="search-button" type="button" class="btn btn-primary">
7    <i class="fas fa-search"></i>
8  </button>
9</div>

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