First, shaky leaves are just hints - NOT real DNA matches. The trees may or may not be accurate or matched to the Common Ancestors you share. In my experience they are about as accurate as the shaky leaf hints in the non-DNA part of Ancestry. Mine seem to run about 60% accuracy.

If you want real matches you can verify, either upload your raw data results to GedMatch (basic services free, but currently not working) and/or FamilyTreeDNA for $39.

If you want to learn more, Richard Hill has an excellent e-book "Guide to DNA Testing" available on Amazon.