Google Scholar. Try using this to limit your search to scholarly sources.
Google Advanced Search. You can search within a particular domain eg .gov.uk. This will limit your search to UK government publications.
Or, instead of searching the Internet, go directly to the source. We have selected some websites here that could be useful to your search.
"Double quotation marks". If you're searching for the title of a document or searching for a phrase, enclose your search in "double quotation marks".