Sometimes, your child may just be saying in heir own way that they need your attention at that moment. See if you can read the emotion in your child's eyes and body language. Kids have facial expressions or body language that can help you determine what they are feeling. This means really listening. It means putting down the paper, turning off the television, putting aside what you are doing and listening.
All kids have moments when they are receptive to talking to their parents.
If you ignore these moments, the child may not remember or want to talk again. You may not agree with what your child is saying or the behavior being exhibited. But it is important to validate the child's right to have the feelings. Don't lecture, don't try to solve the problem, don't offer advice. It is the most important thing you can do.