Here is a list of internet tools which can be use to search literature on the internet. Practice and spend time  you will be learn automatically.

1. High Wire Press http://highwire.stanford.edu  

2. Google Scholar http://scholar.google.com/  

3. Sciendedirect http://www.sciencedirect.com/

4. NCBI Pubmed http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed

5. www.Google.com  use various stings and adavance search option for excellent search results.

6. http://Nature.com

You can find reviews, research articles, reports, updates and letters etc from these search engines.