Steps in a SciFinder Research Topic search
Concepts => The SciFinder search algorithm identifies "concepts". What is a concept? That depends on your search. Really, it depends on your search! It can be a single word or a phrase. Examples below will clarify.
Three simple rules
The first rule addresses concepts
The 2nd and 3rd rules deal with syntax.between concepts
Best terms => The first rule is deceptively simple. There are two types of "best terms" -- (1) Terms that SciFinder uses for a concept (aka controlled vocabulary) and (2) Terms that researchers use (aka "jargon"). The controlled vocabulary of SciFinder is found in the Indexing terms in a SciFinder record. The terms used by researchers shows up in the article title, the abstract, and the uncontrolled portion of Index terms in SciFinder. Yes, index terms in SciFinder use both controlled vocabulary and uncontrolled vocabulary!
Experiment with different words to find what works best. It may take a couple of searches (or even weeks or months) to find the best terms for your search needs. For example, CAS Registry Numbers are usually better search terms than common names.
Identifying the "best terms" also depends on your chemical knowledge -- as your understanding of a topic improves, often so do your searches.
The "parenthetical OR" can be distributed over a preposition.
"mercaptan (thiol) with electron transfer" would be interpreted by SciFinder as meaning ...
"mercaptan with electron transfer OR thiol with electron transfer".
Combining searches can be a good way to narrow a search.