It is important to adopt a flexible approach when choosing a topic to investigate. The goal when writing any research paper is to choose a research problem that is focused and time limited. However, your starting point should not be so narrowly defined that you unnecessarily constrict your opportunity to investigate the topic thoroughly. A research problem that is too narrowly defined leads to any of the following:
You don't find enough information and what you do find is tangential or irrelevant.
You find information that is so specific that it can't lead to any significant conclusions.
Your sources cover so few ideas that you can't expand them into a significant paper.
In general, a research problem is too narrowly defined if you can't find any relevant or meaningful information about it. If this happens, don't immediately abandon your efforts to study the problem because it could very well be an excellent topic of study. A good way to begin is to look for parallels and opportunities for broader associations that apply to the initial research problem. A strategy for doing this is to ask yourself the basic six questions of who, what, where, when, how, and why.
Here is an example of how to apply the six questions strategy to broaden your topic. The research problem is to investigate ways to improve trade relations between Peru and Bolivia. Ask yourself:
Who? -- Are there other countries involved in the relations between these two countries that might want to challenge or encourage this relationship? Are there particular individuals [e.g., politicians, union leaders, etc.] promoting trade relations or trying to inhibit it? [remember to ask both the individual who question and the collective who question].
What? -- What are the specific trading commodities you are examining? Are there commodities not currently traded between Peru and Bolivia that could be?
Where? -- Ae there examples of other bi-lateral trade agreements that could model the potential for closer trade relations between Peru and Bolivia? Note that the question of where can also relate to spatial issues, such as, are there geographic barriers impeding transportation of goods?
When? -- How long have these countries had or not had trade relations? How far into the future might a trade relationship last given other factors?
How? -- How might Peru and Bolivia forge these ties in relation to, for example, long-standing internal conflicts within each country? Note that the how question can also be framed as, "In what way might...." [e.g., In what way might improved trade relations lead to other forms of economic exchanges between the two countries?].
Why? -- What advantages can each country gain by pursuing active trade relations? Why might other countries be concerned about closer ties between these two countries?
Reflecting upon these six questions can help you formulate ways to expand the parameters of your initial research problem, giving you new ideas that can be investigated. Once you've found additional directions in which to proceed with your topic, you can try narrowing it down again, if needed.
NOTE: Your initial review of the research literature can help you answer these questions as well as identify gaps in the literature when answers cannot be found.
Coming Up With Your Topic. Institute for Writing Rhetoric. Dartmouth College; Getting Started With Your Research: A Self-Help Guide to Quality Information, Jean and Alexander Heard Library. Vanderbilt University.