Doors won't lock

[Garagedude]

The doors will never lock, I bought the truck last year and haven't driven on the street yet, but am getting ready too, I would like to be able to park it in a parking lot and know that somebody is not going though my cab. When I close the door and try and lock it the I can't push the thing all the way down and when I can, I can still open the door, anyway i have this problem on both sides, I was looking into buying new latches and strikers, but is that the problem or is this just an adjustment type thing. I hate lining body panels up and doing this type stuff. Thanks Steffen