What in fuck's palace of fuckery do you even mean by covering his tracks? His companies have been charged with laundering Russian money. Two borderline treasonous meetings are public as shit. None of this has been skillfully concealed at all.
And the investigation is happening. If it is leaving plenty of traces, and rises to the level of the sort of crime the FBI would write a (sealed) indictment for with a recommendation to congress, then that's what will happen. Or, it won't rise to that level. We don't know yet. You're begging the question with perjury trapping. That's a very common investigative technique at the political level no matter how guilty the suspect is thought to be. You're just really wrong about all kinds of things.
At least now you'll think twice before characterizing legitimate public concern over Trump campaign and Trump org activities in the outrageously cartoonish way you've been characterizing them. You'll do it anyway, because that's the kind of person you are. But you'll think twice.
And... no tracks leading directly to Trump? Well thanks for proving my point; case closed, shut it down.
You see, in order to collude with a foreign country like Russia to win an election, you'd actually have to make contact with them to get your instructions; consistently, multiple times throughout the process (common sense really). Whether it be by email, telephone, social network, telegraph, what have you... these leave tangible traces the intel agencies could pick up; there are no such messages revealed up till now, because they don't exist.
If you want to see what a real investigation looks like, pay attention to the recent scandal involving Obama's DOJ and top FBI officials; take notes, ya might learn something. Tangible traces consistent throughout their collusion, as with the over 50,000 text messages uncovered, which they tried deleting (in spite of no electronic messages truly being deleted from those in the intel agencies). They have all the evidence they need already; it merely falls on Sessions now to drop the hammer. So quick and easy in comparison.
Not everyone falls victim to doublethink. It takes a special kind of person to believe a conspiracy theory of such transparent magnitude that it would even put Alex Jones to shame.