1.   Analyze the language of your research problem.

2.   Look for precise or unique words that are likely to lead only to code sections that will answer your problem.

3.   If your first use of the index proves fruitless, make sure to exhaust all synonyms and related terms at varying levels of abstraction.   (You might want to use a legal dictionary or a legal thesaurus to generate synonyms and related terms.)

4.   Scan the entries in the Index.  If the answer is not apparent, check whether the entries under one topic suggest other topics to look up in the index.  Follow up on all 'see references' that might be relevant.