Our antennas have a digital VHF and a digital UHF range that vary based on the style of the antenna.
Since 90% of the towers in the US are transmitting in digital UHF most digital antenna companies design their antennas to pull in those signals most efficiently. There are still a few towers that are transmitting in VHF and that can be a little more challenging. VHF signals are always numbered 2 - 13 so if you are getting all the stations that are listed in your area with the exception of a station with one of those number they are transmitting in VHF and you may need a larger antenna. Here are the UHF and VHF ranges for our antennas.
Leaf Metro and Leaf Mini: 25 mile digital UHF range / 10 mile digital VHF range
Leaf 30, ReLeaf and Curve 30: 30 mile digital UHF range / 10 mile digital VHF range
Leaf 50 and Curve 50: 60 mile digital UHF range / 20 mile digital VHF range
Sky 60/Leaf Glide: 75/65 mile digital UHF range / 45 mile digital VHF range
One thing that some people do to be able to pull in the VHF stations that they desire but are not able to get with their digital antenna is add a set of rabbit ears to their set up. Using an A/B switch allows you to connect two antennas to your TV. The Mohu antenna for the digital UHF and digital VHF signals that are in range and the rabbit ears for the VHF signals that are out of our antenna's range. You would "switch" from A to B depending on what channel you were wanting to watch at the time. It can be cumbersome but it is a way to get the channels you'd hoped for. Here's a photo of an A/B Switch for reference and they can be purchased at any retailer that sells electronics.