Systems and methods for automatically retrieving and providing digital advertisements from multiple channels with improved relevancy to a search query are disclosed. In some embodiments, based on a query, a first set of sponsored items is retrieved and ranked based on an optimization of conversion rate, and a second set of sponsored items is retrieved and ranked based on an optimization of click-through rate. Based on the first set of sponsored items and the second set of sponsored items, a ranked list of recommended items is generated for display based on an advertisement auction mechanism, in response to the query.