Hello Dragoljub,
hold ctrl key, click x1 left mouse button on each file to select, release ctrl key when all wanted file selections are made, do not click mouse in the window.
You can now scroll mouse using centre wheel.
If you wanted to scroll and select more files, then after scrolling, again press and hold ctrl key and x1 left click on each file to add to previous selections from above.
That is not to scroll whilst holding down ctrl key, it will resize all folders and files up/down dependent on forward /backward scrolling etc.
hold ctrl key, click x1 left mouse button on each file to select, release ctrl key when all wanted file selections are made, do not click mouse in the window.
You can now scroll mouse using centre wheel.
If you wanted to scroll and select more files, then after scrolling, again press and hold ctrl key and x1 left click on each file to add to previous selections from above.
That is not to scroll whilst holding down ctrl key, it will resize all folders and files up/down dependent on forward /backward scrolling etc.