Failed to Search Exception

[sandeepmd1]

I'm observing intermittent behavior with the exception 'java.util.concurrent.ExecutionException: com.basho.riak.client.core.netty.RiakResponseException: Failed to search'.

Facing this exception while doing search operation using Riak client.

May i know in which situation or condition we do face this particular exception with the error message "Failed to search".