I agree that there's just not enough information to determine what to look for in identifying the suspect's vehicle.
The only description of the vehicle is from the Dec. victim, and she could only describe interior features. We don't have make, model, color, year, or any of the other factors that make up a vehicle description.
Also, in this day and age, many people own more than one vehicle. If the suspect has another vehicle, the one used in the Dec. attack might be parked right now with all the publicity.
I hate to says this, but right now it seems to be a "looking for a needle in a haystack" situation. It appears that there's just not enough information to identify the vehicle or the killer.