Probably needs new printer heads. Some times they are replaceable but quite often they are almost as expensive as a completely new printer which is why many people tend to discard their printers rather than fixing them once they start exhibiting problems.
I would start by cleaning the printer heads manually, i.e. by using cotton buds and ethanol. You probably need to take them out to do it properly. Soaking the heads in ethanol for a little while could also help dissolve any gunk. Afterwards let them dry a bit before reinstallation.
Edit: If you were in doubt, the printer heads is the part below the ink cartridge. Often they are a part of the assembly where the ink cartridges are installed into so it may be quite a large piece that needs to be replaced.