I am really at a loss of words to describe my problem, so apologies in advance for the poor choice of words in the title.
Basically I have this component at the rear wheel (which I think is called rear derailleur):
and how far it is from the spokes of the wheel is controlled by the springs(?). The trouble I have (as it seems) is that this component is too "loose" causing the chain to not be able to catch on to the component's "wheel" properly.
And notice how in the former case, the chain doesn't lie flush with the "component"'s metal wheel. So that when I cycle the pedals, the chain always unhooks and causes a jam.
Is there any screw etc. that I can adjust to keep the component "pressed in", presumably something to do with the spring..