Why Didn’t Robert Mueller Subpoena the DNC Servers Beginning His Investigation so Doesn’t that Show Coverup?

Translate:

If special counsel Robert Mueller were an honest investigator, he would’ve subpoenaed the DNC’s servers at the beginning of his investigation into Russian meddling, but instead CrowdStrike, hired by the DNC, did their own investigation, so CrowdStrike apparently provided the supposed evidence to indict the twelve Russians, paid by the DNC??