What Are You Searching?
Identify whether you are searching the full text of the articles or just the indexing information (title, author, abstract, etc.).
Because of the limitations of full text searching, it is often better to browse particular issues of publications. This allows you to understand the context in which an event occurred, observe items like advertisements that are often unindexed, and discover vital pieces of information missed through searching.
Over time, the spelling of words, particularly proper nouns, may change. Use reference sources and context to account for any variations in spelling over time.
Transcription vs. OCR
Has the original source been transcribed, or has it passed through OCR (Optical Character Recognition) software? OCR software can mistake letters or interprets defects in the source paper as additional letters.
Limit to First/Lead Paragraph
If the number of results is overwhelming, try limiting your keyword search to the first or lead paragraph. This will eliminate results in which your term is mentioned in passing. Keep in mind that this may exclude valuable information.