Now let's review what Democrats are saying about what Mueller said. They're saying that Mueller "told them," to go forward with further investigations and impeachment. He didn't tell them to do anything with the report just that his job was done in reference to it.
Some of what Mueller said was dangerous and divisive. It's so outrageous that the head of our country's law enforcement doesn't understand the impact of not having sufficient evidence. Judges don't allow cases to move forward if the prosecution doesn't have enough evidence to try a case. People are innocent until "proven," guilty. Contrary to what Mueller was saying, Trump doesn't have to prove his innocense, the prosecution must prove guilt.
So the bottom line is that the Mueller Investigation took over two years and was beyond thorough. Mueller was saying, in so many words, that his team is done but if Congress wants to try and find something that's up to them. But what in the world could they find? Just exactly what questions could they ask the same people Mueller's team has interviewed that would get different answers? Members of Congress aren't law enforcement professionals.
Let's face it, they wouldn't ask many questions anyway, they'd do what they always do and use their five minutes to grandstand. They'll make ridiculous, unverifiable claims, and ask the person who is supposed to be being interviewed just a couple of leading questions. We all know they don't get anything done in these hearings. U.S. citizens deserve better.