How can I search for OP_RETURN data? Is there any way to check for this data in blockchain? 

I want to search this value: 554e6963444320 and want to return this transaction https://blockchain.info/tx/7e92e90f221ad28daf42b5b8bda4c8e244e37af48527fcd12b2518db5d3315bd
The Chain.com API offers functionality for returning OP_RETURN data by:


Address
TxID
Block height


The JSON return data from the REST API has a text field which is meant to be the decoded hex data sent (ie 6a``hex data) but it's returned in the format \\x``hex data.

In Python you can simply do this:

import __future__
import requests; from binascii import unhexlify
rdata = requests.get("https://api.chain.com/v2/bitcoin/addresses/%s/op-returns?api-key-id=DEMO-4a5e1e4" % "1Bj5UVzWQ84iBCUiy5eQ1NEfWfJ4a3yKG1") # substitute URL here
assert rdata.status_code == 200
jdata = rdata.json()
hexdata = [unhexlify(str(t["text"]).encode("utf-8"))) for t in jdata
print(hexdata)