Keyword Research - A Secret Trick Most People Don't KnowBy Michael Ullman

If you're going to enter into any niche, you should start broad, then go narrow. This ensures you won't miss important keywords. For example, let's say you were going to do keyword research for dieting tips. To start broad, we'd want to research a term like diet. We are not looking for just keywords with diet in them however, because search engines like Google also analyze relevancy by latent semantic indexing (LSI). What LSI means is that search engines check for similar terms related to diet to determine how relevant the content website is.
To take advantage of LSI properly, do a Google search for diet, but put a tilde (~) in front of the term, so search would look like this: ~diet. Google will return related words in bold such as weight loss, recipes, wheat, meal, eating and foods. Notice the difference from these words and words you'd find in a thesaurus. If you're doing keyword research properly, your best to use terms that search engines tell you are relevant, and not what a thesaurus suggests. [ read more]