Bootstrap Select

<!--Default Usage-->
<select class="selectpicker" data-style="border">
  <option>Mustard</option>
  <option>Ketchup</option>
  <option>Relish</option>
</select>

<!--select boxes with group -->
<select class="selectpicker" data-style="btn-raised-default">
  <optgroup label="Picnic">
    <option>Mustard</option>
    <option>Ketchup</option>
    <option>Relish</option>
  </optgroup>
  <optgroup label="Camping">
    <option>Tent</option>
    <option>Flashlight</option>
    <option>Toilet Paper</option>
  </optgroup>
</select>

Bootstrap Live Search

<!--Live Search-->
<select class="selectpicker" data-live-search="true" data-style="border">
  <option data-tokens="ketchup mustard">Hot Dog, Fries and a Soda</option>
  <option data-tokens="mustard">Burger, Shake and a Smile</option>
  <option data-tokens="frosting">Sugar, Spice and all things nice</option>
</select>

Limit the number of selections

<!--Limit The number Of Selection 1-->
<select class="selectpicker" multiple data-max-options="2" data-style="border">
  <option>Mustard</option>
  <option>Ketchup</option>
  <option>Relish</option>
  <option>Cheese</option>
</select>


<!--Limit The number Of Selection 2-->
<select class="selectpicker" data-style="border" multiple>
  <optgroup label="Condiments" data-max-options="2">
    <option>Mustard</option>
    <option>Ketchup</option>
    <option>Relish</option>
  </optgroup>
  <optgroup label="Breads" data-max-options="2">
    <option>Plain</option>
    <option>Steamed</option>
    <option>Toasted</option>
  </optgroup>
</select>