Google will display more ads for commercial-related keywords in its paid search results than in its non-commercial results, Google said last week, DM News reports. More ads will be displayed for keywords that are more commercial in nature, such as "running shoes," than for noncommercial, educational-type queries.

"Over the coming weeks, we'll be implementing an ads quality change designed to show fewer ads on queries for which our users might prefer not to see them and more ads on queries for which ads are useful. The impact of this change will vary from advertiser to advertiser, so we wanted to give you a heads-up and suggest that you keep an eye on your keyword performance over the next few weeks," Nick Fox, product manager for ads quality at Google, wrote on Google's "Inside AdWords" blog.