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I'd chalk it up to being a quirk. "Golf holidays" is the keyword that actually has volume, therefore anything happening on "golfholidays" is mostly a curiosity unless you can track conversions from it. I would ignore it and keep plowing forward with your efforts to rank for the one you care about. More likely than not you just need to keep building the authority of your site and make sure your page is well optimized for the phrase "golf holidays" and you'll get there. Most of the sites I see ranking on page 1 for that query have a decent number of links to them. 5 results are homepages which tend to have more links than internal landing pages, and the landing pages that are ranking are reasonably well targeted. As an example of what it takes to show up with a well optimized internal page with no links - British Airways (https://www.britishairways.com/en-us/destinations/holiday-types/golf-holidays) is only ranking 10th for the query with a highly authoritative site.