"I was thinking more along the lines of doing some research" - in this context "along the lines of" is used to present a different idea. e.g.:
Person 1: "For the project, why don't we start by making a presentation?"
Person 2: "Well, I was thinking more along the lines of doing some research."
In other contexts, it can be used in a way which means 'similar to'. This example is from the Cambridge Dictionary:
"They're campaigning for the electoral system to be reformed along the lines of (= so that it becomes similar to) the one in Germany."
Hope that helps!