How to handle not to answer back,if doesn't match.

I want to control ,not to answer anything back,if doesn't match.Can i?
[Link-stackoverflow](http://stackoverflow.com/questions/41008887/why-wit-ai-is-keep-replying-something-even-not-matches)

<img width="1018" alt="screen shot 2016-12-07 at 9 50 36 am" src="https://cloud.githubusercontent.com/assets/16178522/20955444/a30662a6-bc71-11e6-825c-c472ede73242.png">
