twitter bootstrap autocomplete dropdown / combobox with Knockoutjs

Have a look at Select2 for Bootstrap. It should be able to do everything you need.

Another good option is Selectize.js. It feels a bit more native to Bootstrap.

Does the basic HTML5 datalist work? It's clean and you don't have to play around with the messy third party code. W3SCHOOL tutorial

The MDN Documentation is very eloquent and features examples.

Select2 for Bootstrap 3 native plugin

https://fk.github.io/select2-bootstrap-css/index.html

this plugin uses select2 jquery plugin

nuget

PM> Install-Package Select2-Bootstrap