What are some of the smart ways of finding related literature online
I prefer using advanced searches in digital library sites like ACM-DL, IEEE Xplore, and Elsevier ScienceDirect. 

For instance when you search for a particular keyword (e.g., image retrieval) in general search, you would be bombarded with many papers related to the keyword. While most of which is not even directly connected to he matter. In advanced search, you are given the feature to add constraints such as searching for "image retrieval" only within the title. Although this might remove some of the actually related papers, you could be assured that nearly all of the papers resulted from this search is directly connected to your keyword.