Google announced yesterday that they are expanding the search queries for health or medical symptoms to show you related queries.
This way if you search for something too specific, such as headache on one side, Google may show you related searches to pick from such as "headache," "migraine," "tension headache," "cluster headache," "sinusitis," and "common cold."
Google added:
We create the list of symptoms by looking for health conditions mentioned in web results, and then checking them against high-quality medical information we’ve collected from doctors for our Knowledge Graph. We worked with a team of medical doctors to carefully review the individual symptom information, and experts at Harvard Medical School and Mayo Clinic evaluated related conditions for a representative sample of searches to help improve the lists we show.
Google said this is rolling out on mobile over the next few days, in English in the U.S. to start and will expand from there.
Forum discussion at Google+.
