Below are some particularly useful search commands for searching in Google
What it does: Searches within a specific site or domain. Useful for locating information from specific government organizations. Also useful for locating materials more generally from .gov or .edu domains.
Examples: site:who.int or site:.gov
Notes: Be careful if searching for site:.edu. Not all websites that end in .edu are universities or other educational institutions, the domain can be used by anyone.
What it does: Searches for specific file types. Useful for looking for reports, white papers, working papers, or factsheets.
Examples: filetype:pdf
Notes: There may be information you are missing if you limit to one filetype!
Example search: Lyme disease site:who.int filetype:pdf
What it retrieves: This search retrieves pdf files published to the web on the WHO website.
Example search: bt corn site:usda.gov
What it retrieves: This search retrieves any information on bt corn on the USDA website.