Research - how do you define it?
Evidence based practice defines 'research' as the creation of new knowledge through studies or trials. (Some folks include surveys and questionnaires. See Research Types.) You could think of this as Research with a capital R.
Looking up studies and trials is defined as a 'literature review'. You could think of this as research with a small 'r'. It is what we do when we want to find out what is already known.
When practicing evidence based nursing, you usually have to perform a literature review. You seldom actually have to 'do' Research.