Hi @DEcheverria,
There are a few different ways to approach this, the by far easiest way would be creating lists (especially if the list of fields is short).
One option would be creating active lists. Let’s take for example First name, Last name, Phone number. Create a list named “Incomplete name” with a list filter “First name is unknown OR Last name is unknown”, another list called “Phone number missing” filtering for “Phone number is unknown” etc.
(For a list of contacts who are missing a value in any of the fields, connect the criteria by OR. This could be a recipient list for an email campaign, trying to get these contacts to submit a form with their full information, for example.)
If you’re actually referring to “no value” spelled out instead of an empty field, you would simply filter for “First name is equal to any of no value”.
The same approach works for filtered views (Menu > Contacts > Contacts > More filters) and for actual reports (Menu > Reports > Reports > Create custom report > Single object > Contact).
Let me know if you have any follow-up questions!