The text of a document, tombstone, etc. communicates information about a person or an event. Sometimes that information is explicitly stated, sometimes it is implied–if we interpret the document in addition to reading it. But there may be more than just words on a record. Are there other “images” on the source you are looking at that also communicate information? A funeral card, memorial card, or tombstone may have images that are symbolic and not just decorative filler.
A document may also have numbers written on it that have meaning as well. Twentieth-century death certificates in the United States have numbers that indicate information about the cause of death. There may be numbers on a court paper or record that indicate a file number, docket number, etc. Or the number may be a calculation made by a clerk that has nothing to do with the case.
Other numbers may be written on land patents, pension records, or bounty land applications that have meaning as well.
Everything on a document has the potential to be a clue. Look at more than just the words with obvious meanings. Sometimes it is the not-so-obvious meanings that provide the biggest clues.