A well written technical document has to follow rules of structure and present a minimal amount of elements such as textual elements, theme, theme/problem, research hypotheses, justification, objectives, examples of verbs for objectives, theoretical reference, methodology, schedule, and resources. Most valuable documents presents a compilation of those elements.
The theme of the technical document is a monographic study, it seeks to solve a problem, the more specific it is, the better. Delimiting the theme, the author can show how he became interested in the subject.