To prevent overlapping labels in your series or to display labels of one series above the line, you can proceed as follows. You can select all labels of one series by a simple or double-click on one individual label (according to the user settings). You can place the labels by drag & drop at the bottom sticky position.
To select only specific labels in a range (and subsequently to move or format), you can select the first label with the Shift key pressed down and click the label at the end of the desired range. This gives you the option to move or format the labels in the desired areas.