Firstly: Research questions focus your topic from something very large into a more focused query that you can answer in your assignment. Sometimes assignments focus on a single large research question, others build in multiple smaller questions.
"Gun Control?" is not a research question. "Do assault weapon bans decrease violent gun death?" is a research question.
Secondly: Research questions allow you to use multiple concepts to create a more powerful search. Databases don't always produce good results when searching for a single concept.
I would type "assault weapon ban" and "gun death" and into LionSearch, or a similar database to research this question.
Focusing the Scope of a Topic
It is very easy to go overboard with really big ideas! Remember, a quality topic is one that you can address thoroughly in the full length of your assignment. Avoid single concepts, generally. Some examples are:
Entire wars or conflicts.
Social issues that are constantly discussed (ex. abortion, or legalizing marijuana)
Instead think about focusing on:
How a specific group was affected by a war (ex. how children were affected by conflict in Iraq)
A specific element of a social issue (ex. how the criminalization of marijuana has affected black men)
It's also very easy to get an idea that is so focused that it is essentially impossible to research, often because scholars just haven't looked at that issue yet. Check when you pick a topic that you can find a variety reliable sources on what you plan to address. Some examples are:
Why a little-known athlete is underrated.
How a single video game should receive more awards.
Instead, think about focusing on:
The system that allows excellent athletes to be ignored despite excellent performance, using your athlete as one example.
The flaws in the system of evaluation for video games, using your game as one example.