Library Search is a good starting point.
You can easily retrieve details of print and electronic books, journal articles and other full text material.
To research the global literature on a topic, and go beyond quick full text results, then you should follow up with a database search.
You can tailor your search more precisely using all the sophisticated functionality available on the research databases.
Google is a great tool for examining certain kinds of material such as blogs and other openly accessible web resources. However, the information you find will vary greatly in terms of accuracy, currency and bias. Always evaluate the material for research quality.
As well as containing information that is not exposed through Google, the Library research tools also allow you to be more precise with your searching- they offer specialist features to improve your research discovery.