Google Advanced Search Interface: https://www.google.com/advanced_search
FYI, most advanced searching features will work in most internet search engines. Many of these also work within literature databases!
When you use quotations, internet search engines search for that phrase, not each word separately.
"microbial ecology" vs microbial ecology
Searching Sites and Domains
the "site" options mean that you can restrict the search to a specific website. Similarly, you can restrict your search to a specified DOMAIN, such as .edu, .gov, .org, or .com
example search using the above two strategies:
"spinach contamination" site:fda.gov
compare this search to:
"spinach contamination" site:.org