In the results list, each published ad has a trash button that opens a confirmation. Deleting removes the ad permanently from Meta Ads Manager. To delete several at once, select the checkboxes of the rows you want (the header checkbox selects all, and Shift + click selects a range), then click Delete Selected in the bar that appears. The window shows the progress of the deletions and tells you if any failed. Each row also has an Edit button, which opens the ad directly in Meta Ads Manager. The trash button in the header (Clear logs) only clears the list on screen and does not delete anything in Meta.