Most people will probably be familiar with paint and that thin layer of plaster/render (with little bobbles in it) coming away from internal walls. When you touch it, even more comes off.
Every year I use a white filler to try and fill it but the filler never seems to adhere to the wall for longer than about six months. My smoothing process isn't brilliant, nor are my attempts to re-create the bobbles.
So my question is what should I be buying in Leroy Merlin (or other suppliers) to eradicate this problem for good? With spring around the corner I'd really like to have one last attempt to get it right and would appreciate recommendations for the products I should be buying.