Return relevant news articles to a search term

Using an RSS feed (or some better technique) I want to return relevant news articles to a search query. So, given an entry in a search box on a webpage, return all related news articles. I need articles from many different high-quality news sources, such as AP, reuters, BBC, yahoo, marketwatch.... etc. I would like this to be programmed primarily in PHP. Use of js,json,jquery,ajax..etc can be used to increase functionality if needed. The news articles need to come from many different sources (not just from one RSS feed), but I only want quality and highly relevant articles. I'm not sure if RSS is the right approach. I basically want to get content that would appear on a popular news portal site (such as DrudgeReport), but relevant to a search query. Also, the most recent and most relevant articles should appear at the top of the list. For example, if somebody searches microsoft; I want all relevant and recent news articles about microsoft computer company returned. The results should be ordered by relevance to the keyword and by how recent they are ( newest articles first).