Bootstrap Select

plugin that brings <select> elements into intuitive multiselection, searching, and much more.

Check out Github

Launch modal examples
Basic examples
Select boxes with optgroups
Live search
You can add a search input by passing data-live-search="true" attribute
Add Key words to options to improve their searchability using data-tokens. Try car, fruit
Custom button text
Set the title attribute on individual options to display alternative text when the option is selected:
select count
select count>3
show-tick class
Customize options
DashboardKit Customizer
Header settings

Sidebar settings

Layout settings