If you use Google Analytics and notice that some keywords under
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have zero visits yet are displayed in the table. The zero visits and zero pageviews per visit appear puzzling because how can a keyword with no pageviews appear on the stats table if the one who used the keywordt did not ended up not visiting any of your pages (hence, the zero pageviews):
Google Analytics uses a campaign cookie method whose session lasts for 30 minutes. Within this session, the information on keywords previously used will not be recorded to avoid inflating the visit numbers.
For example, if I searched for “Phoenix Suns” at one point in the session and entered the site, then later uses the search phrase “Phoenix Suns tickets”, “Phoenix Suns” phrase will get zero pageviews and zero visits while “Phoenix Suns tickets” will carry the visit and pageview numbers until another keyword referrer is used to reach the site within the same session.