Can you add sorting method or attribute?

[aQua-pl]

Can you add sorting method or attribute to multiple select boxes, sort the result according to the order selected in multiple select boxes?

For example:

<select class="selectpicker" multiple>
  <option>Mustard</option>
  <option>Ketchup</option>
  <option>Relish</option>
</select>

I chose Ketchup,Mustard and Relish successively,the result is Mustard, Ketchup, Relish.I want the results to be Ketchup,Mustard,Relish by adding the sorted method or attribute.