The first one is a puzzle, and there shouldn't be anything at the posted coordinates. You'll have to solve the puzzle to get the correct coordinates.
When I StreetViewed the second one, it shows as being near the west side of the road, and there's only one thing I can see there that you could hide a cache in/on.
For any cache, the device you're using will usually only get you to within about 30 feet of the cache, due to inaccuracies in your and the owner's devices. When it says you're close, put it away and start looking for places where you could hide something. With time and practice, you'll be able to spot the hiding spots from miles away, even if the GPS is pointing somewhere else.
See above about the specific Neanderthal cache, but I'll mention something from the guidelines:
It's pretty universal that caches will not be allowed under overpasses or on freeway bridges. There are a couple of reasons for this:
1. Safety - Usually, to get to such a spot, you'd have to pull over on a freeway. This is not only potentially dangerous, but is illegal in places.
2. Terrorism - If someone were to spot a suspicious container under a freeway overpass, it could be mistaken for a bomb. Many a cache has been destroyed by bomb squads because it was hidden in a suspicious spot.
It's a good idea to at least scan through the guidelines to educate yourself on what is allowed or not allowed. By knowing where a cache can't be, it can help narrow down where it could be.
Thank you both! I will continue to learn! I get frustrated with these little ones...so I go off into the woods and find some bigger ones to keep me fed!