Research is a systematic method of inquiry to gain knowledge. This knowledge might be an answer to a question or problem, or if may be descriptive, telling us what about a process. You have a structured method for how you will conduct the inquiry and gather your data. Having a structured methodology is necessary to provide guidance to other researchers who might want to try to reproduce the results. If the results happen only once, then those results may have been in error, or at least cannot be applied universally.
Another way of describing research is to say that it is the application of scientific method to a problem or question.