Garmend used their advertised product report and found several ASINs with much higher ACOS than the rest of their products. What can they do to help lower the overall ACOS for the campaign?

Removing underperforming ASINs with high ACOS directly addresses the problem by eliminating products that are spending a lot without generating proportional sales. This action immediately improves the campaign's overall ACOS. Increasing visibility by adding more ASINs or keywords might increase impressions and clicks, but if those additions also have high ACOS, the overall campaign ACOS could worsen. Increasing bids on high-performing keywords is generally a good strategy for scaling successful products, but it won't directly lower the ACOS of the underperforming ASINs; it would only increase spend on already well-performing areas, potentially masking the issue of the high-ACOS ASINs.