The investigation is ongoing, it took years of investigating Benghazi to find the email server, which is ultimately what did Hillary in.  It took damn near a year of investigation to find the tapes on Nixon, the Ken Starr investigation of Bill Clinton took 3 years to find the blue dress.  So, while you seem to think that this is over and done with, realize that these things take time, and quite often they find something completely different than what they originally were looking for.  Ultimately I do think that what they are going to find is that Trump's campaign, without his knowledge did actively work with a foreign government to help Trump win, and that Trump's own ego and inexperience is going to land him an obstruction of justice charge for trying to sway the investigation.  As for blaming the Ds, realize that the Ds hold ZERO power in the House or Senate, and that the Rs could decline to hold hearings, that the Rs are holding them should tell you something.