I agree, that is true. If they do not have notoriety they will not be “out there” and documented on the net. And some on a global scale have made sure they have no connections or searchable information. There are some entities very globally important yet they don’t even have a wikipedia page. So you have to dig harder in places where they may have forgotten to cover their tracks. Places they are proud of like having their name on a college alumni list or community project donor list then work backwards. College alumni lists are great for them bragging about their bio background and who they worked for/with and such.
Trust me on this: a clear ethics violation or conflict of interest can be close to a silver bullet because it tends to cause defections and genuine angst, while tagging someone as a liberal is commonly less useful because it is already known to a target candidate’s core supporters.