To force one or several products to appear first in a product list
To bring a product on top, you need to create first your Rule and connect it to the right widget (see topic 1 for support on this)
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Alternatively, you can simply include or exclude the product (instead of ranking it), Include just make sure it is part of the results, but doesn't affect its position and exclude removes it from the product results. Finally you can use the option "boost" if you want to promote it with a specific weight (see the weighting of your Scorers in your TPO WPO Strategy for more details about boost weights and the scoring formula).