When I read something in a novel that invokes the sense of smell, I realise how under-utilised it is in writing. We spend pages describing how things look, and often overlook (pun intended) smell.
Smell evokes strong memories, and is probably the best of our senses for accomplishing that. I recall walking along a street and smelling pipe tobacco (a lot of years ago), which brought back memories of my grandfather. I hardly knew him as he died when I was young, but that momentary smell was enough to recall not only him, but also his house, and a holiday we had spent there.
Look at places in your writing where you have description, and see how you could include smell, not only for recollection, but also in deepening the sense of place and setting, or even character description.