On Amazon, if you want to view the sales ranking of a certain product, you can follow the steps below:

Open the Amazon website and search for the keywords of the product for which you want to view the sales ranking.

After entering the search results page, you can select "Sort by" under the filter column on the left, and then select the "Sales" option.

After the sorting is completed, you can see the top products ranked by sales in the current search results.

Please note that Amazon's sales ranking changes in real time, so the sales ranking viewed at different time points may be different. In addition, Amazon may also set different ranking rules according to different regions and categories, so the same product may rank differently in different regions and categories.