Hi, I want to introduce you two options and anyone who has experience with SEO would say what he thinks is best way to get the best position for the keywords "Online Advertising" on search engines. 1: - Create a page called "Online Advertising" - Link from other sites to the home page using the keywords: "Online Advertising" 2: - Create a page called "Online Advertising" - Link from other sites to this page using the keywords: "Online Advertising"
If your home page is related to advertising then use that, if not make a seperate page for online advertising. Above all find other keywords related to "online advertising" mix and match to make longtail keywords and use them as well.
your both option is right.longtail keyword that idea will be more powerful use that one. If not then, if you can select your other targeted keyword also & use PPC campaign that will give benefit than other option.