Problem with retrieving indexed docs

Hi everyone!
I have this problem when I want to retrieve indexed tweets which contains the word ‘Me’:

C:\Windows\system32>curl -XGET "http://localhost:9200/tweetindex/a_tweets/_searc
h?q=Me&pretty=true"

{
"error" : "IndexMissingException[[tweetindex] missing]",
"status" : 404
}

This is how I tried to index it:

curl -XPUT "http://localhost:9200/_river/mongodb/_meta" -d "
{"type":"mongodb", "mongodb":{"db":"aikin", "collection":"a_tweets
"}, "index":{"name":"tweetindex", "type":"a_tweets"} }"

{"ok":true,"_index":"_river","_type":"mongodb","_id":"_meta","_version":8}

Does anyone had same problem?
Any ideas?