Spotlight needs 5-20 seconds to launch an app

Hello,

is there a way to speed up spotlight? I'm used to use spotlight as an application launcher and in Yosemite this worked perfectly: Enter some letters, the app icon gets displayed, press Return and the app launches. But now It takes from 5-20 seconds until Spotlight reacts to me pressing Return. In fact I'm now faster with manually looking for apps in folders of the launchpad than I am with using Spotlight.

Bye,

Oliver