If you are opening a new tab opening every time you try to place a component it may be that you are in fact not placing the component but are unintentionally opening it for editing.

To select a component from any of the EasyEDA libraries you single Left-Click on it. To place it on the canvas (work space), move the mouse over to where you want to place it then single Left-Click on the canvas. Repeated left clicks will place more copies of the same component.

If you double Left-Click on a component symbol, you will open it in a symbol editor canvas (as opposed to the schematic editor canvas that you wanted).

The situation is slightly different when choosing parts using the Find Libraries... dialogue box via the jigsaw puzzle piece icon on the top toolbar. There, you click on part to place it but have to click Add to my Favorite Parts (if it is from the System Libs) or Clone (if it is from the User Libs). Double left-clicking on it after you have to added it into your personal libraries will then open it for editing.

The same is true for PCB footprints.

:)

After selecting a component, then click the Canvas, you can place it on your work space, click it again will add another. RIght or Esc key to cancel place.

Openiing another tab maybe edit your component