From a simple problem to a complex problem the difficulty is keeping track of the relationships between data points. We can map these relationships with what is called a Mind Map or alternatively a Logic Map The old fashioned way was to use a pencil and paper. Today we have much better ways, and they are free.
The first application that I have found useful for writing is called MindMup. It is available from Google Play, and is free. Free sometimes comes with strings, this one has no strings.
With MindMup you can document your thought process, find where you are (or might be) going wrong. This allows you to adjust your research to better track your logic.
Give it a shot.