You can Drag the mouse from a blank area to draw a box around the icons you want to select, and then release the mouse button.
You can then hold down the Control key and drag around additional icons.
Or, Click mouse button 1 to select the first icon, then hold down the Control key and click mouse button 1 to select each additional icon.
This method is useful when the icons you want to select are not located next to each other.
If you have selected icons in File Manager, clicking or dragging anywhere in the File Manager scrolling pane will deselect those icons. However, if you hold down the Control button before clicking or dragging in the scrolling pane, your existing selections are retainer. This method is useful for making multiple selections.
To deselect icons, hold the Control key down and highlight those icons again; this causes them to become unselected from the group.