Google Scholar is different from Google. Google searches public web content. If your lecturer said not to use Google, they probably meant that they want you to use scholarly resources, not content from the public web.
When using Google Scholar, consider the following:
As a research tool, Google Scholar is good for many tasks, and not as good for others.
Not everything in Google Scholar is scholarly. Google Scholar searches academic websites (.edu) as well as journals and publisher websites. Search results can include powerpoints, news announcements or unpublished materials as well as articles and books.
It is difficult to determine with 100% accuracy all that Google Scholar searches. Therefore, we do not know the breadth of what Google Scholar is indexing and consequently cannot judge the comprehensiveness or completeness of the results of a literature search. Click here for more guidance on how to choose the right sources for your studies.
We cannot tell how frequently items in Google Scholar are updated.
Searching in Google Scholar is imprecise when compared with discipline-specific databases. If your research is needing more comprehensive searching, use individual library databases, such as the ones listed in Database A-Z.