"Limiting scope" means saying, "what I'm about to say applies to just this. You proceed the "this" with 就 (jiù) in this pattern.
"就”可以放在句中以指出主语进行观察、讨论、分析、说明等活动的对象或者范围。
Subj. + 就 + 活动的对象或者范围 + Verb + Obj.
就 (jiù) can be used to limit the scope of a comment, used in the following structure:
就 + Topic + (来说 / 而言) + Comment
This emphasizes that the speaker is just commenting on that particular topic and nothing else, like "just with regards to" in English. In this sense it is similar to 至于, but is generally used to introduce a new idea, rather than to move on from a previous related topic.
Note that in the pattern above, 来说 is more informal, and 而言 is more formal.
When used in this sense, 就 is generally only used in written Chinese.