In A Nutshell
In Depth
Google suffers from two basic problems:
Using Google (and Google Scholar to an extent) will search all types of web sources, not just scholarly ones. It's important to know how to evaluate what you're looking at.
Scholarly databases are better because:
Literature databases usually index several kinds of scholarly writing.
In A Nutshell
Two sources that will help you learn preferred vocabulary:
1. Scholarly articles sometimes (but not always) have a section in the full text labeled Keywords, usually near the Abstract, or at the end of the article under additional information - here's an example - look just at the bottom of the page.
2. Use a literature database such as Web of Science, PubMed, or SciFinder. All these databases show you groupings of preferred vocabulary when you search, although they are called slightly different things in each one.
It should be noted though that Google Scholar, as great as it can be, doesn't offer any help with discovering preferred terminology - it recommends reading secondary sources!
In Depth
You probably know that there are certain preferred words used to describe different things, usually under different circumstances. This is true of both scientific disciplines and databases. For example, take the word plasma. If you asked a physicist to define it, you'd probably get something different from what a biologist or doctor would say (i.e. a state of matter, versus a component of blood).
So, it's important to become familiar with the way concepts and techniques are described in your field of interest. The best way to do this is to read, read, and read some more! Pay attention to the way ideas and experiments are described in the literature. For example, in medicine, you've probably heard of the term "heart attack". Searching for that in the medical literature might get you some articles, but you'd soon discover (especially if you're using PubMed - more on that later) that the preferred term in the medical community is "myocardial infarction". Similarly, in the chemical community, common names of chemicals (for example, polyacetylene) are being phased out in favor of IUPAC names (polyethyne), but if you want to find older articles as well as newer articles, you need to know both!
In A Nutshell
In Depth