Make sure you have a good reason for the check. It will only be accepted to counter vandalism or disruption to Wikimedia wikis. Valid reasons include needing a block of the underlying IP or IP range, disruptive sockpuppetry, vote-stacking, and similar disruption where the technical evidence from running a check would prevent or reduce further disruption.
Be specific in your reasons. Ambiguous or insufficient reasons will cause delays. Explain the disruption and why you believe the accounts are related, ideally using diff links or other evidence.
Make sure there are no local checkusers or policies.
Discussion: There have been severa discussions if Koka11 and Rrjedha have the same user, but the discussions are in Albanian like here and here.
Reason(s): They both contribute with a lot of unencyclopedic stuff and they mainly use Wikipedia as a publishing centre for their personal studies. And please specify every Sockpuppets that these two used. Ammar TivariTalk! 15:55, 16 March 2015 (UTC)
Additional information needed @Ammartivari: Hello. Since I can't read Albanian I had to rely on automatic translation to read the discussions you linked. It seems that in the first one, at the bottom, Koka11 admits that he and Rrjedha do work for the same company or work for the same editorial line. Is that correct? If so, if both are disruptive, why can't them just be blocked without CU? Best regards. -- M\A 12:20, 17 March 2015 (UTC)
Not done. No response. -- M\A 10:00, 22 March 2015 (UTC)