How reliable are search terms for SEO and SEM results?

(Institute for Operations Research and the Management Sciences) With billions of dollars spent each year on search engine optimization (SEO) and search engine marketing (SEM), the power of search terms holds more value than ever. But more than a few digital marketing professionals have become frustrated over the years over the limits just how much can be assumed and predicted based on the search terms themselves.
Source: EurekAlert! - Social and Behavioral Science - Category: International Medicine & Public Health Source Type: news