What visitors type into your own site search bar is some of the most accurate long-tail keyword data available, and most sites never review it.
Export and Review Regularly
A regular look at your site search query log surfaces recurring long-tail phrases your visitors are already using in their own words.
Pay Attention to Zero-Result Searches
A search that returns nothing on your own site is both a missed content opportunity and a validated long-tail term worth targeting externally too.
Cross-Reference With External Research
Terms that show up both in your site search logs and in external keyword research are a strong signal of genuine, sustained demand.
Next step: Use the Longtail Keywords Tool to check whether the long-tail terms surfacing in your site search have broader search demand worth targeting.