Yes, they are doing enough to catch the perpetrators. I strongly believe that the kidnappers are hiding from the police and that is why the police have not yet caught up with them. Given time, they will surely get them arrested. We all understand how it is not easy to catch someone from description.
Yes, the authorities are doing enough to catch the perpetrators because they are doing it without too much media interference. If they announce everything they are doing, they will not be able to catch the kidnappers. They must go about their business quietly in order to catch them when they are not expecting it.
The kidnappers that dumped the California woman at the side of the road after torturing her for an extended period do not want to be caught. Accordingly, catching them will not be easy. It seems, based on public reporting, that there are not a lot of leads and without leads there is little that the authorities can effectively do to find the perpetrators.
Kindnappers are notoriously hard to catch, particularly after the kidnap victim has already escaped. The police and other law enforcement officials are working hard to catch her kindnappers, but they also have to work hard at catching criminals that are still putting other people in danger. They are doing their job.