How search terms work
A search term is the text a person actually typed or spoke into Google. A keyword is the text you put into your account and bid on. They are two different things, and the gap between them is where a Search campaign is won or lost. Google decides which of your keywords, if any, is close enough to the term to enter the auction, and the match type you chose controls how much licence it has to make that leap.
Because that licence exists, one keyword can be triggered by a wide spread of terms: different word order, plurals, misspellings, abbreviations and, on broad match, phrasings that share an apparent meaning without sharing a single word. The result shows up in the search terms report, which lists the real queries next to the keyword that caught each one.
Not every term appears there. Google withholds queries that too few people searched, for privacy reasons, so the report will never reconcile perfectly with total clicks and cost. Performance Max and Demand Gen go further and report grouped categories or themes rather than raw queries.
Why search terms matter
The search term is the closest thing you have to the customer’s own words. It tells you what they call the product, whether they are researching or buying, and whether they wanted a price, a supplier or a repair. Keywords are your guess at that; search terms are the evidence.
They are also the raw material for everything else in the account. Negatives come from terms you should never have paid for. New ad groups come from terms that convert but sit awkwardly under a keyword that is too loose. Ad copy improves when it borrows the wording people actually used. Even outside advertising, the report exposes demand that a landing page or an article ought to be answering.
Where search terms go wrong
The first mistake is reading the report as if it were complete. Withheld low-volume queries, and the grouped reporting used by automated campaign types, mean that absence of evidence is not evidence of absence.
The second is judging a term on clicks alone. A term with clicks and no conversions may be genuinely bad, or it may be new, or seasonal, or badly served by the page it lands on. In a smaller auction such as Nepal, where an ad group may gather only a handful of queries in a week, cutting a term after a thin run throws away signal you have not finished collecting.
The third is presenting a term to a client as though it were a ranking. Someone typed this once and we compete for this are very different claims.
What to do about them
Read the report on a schedule and act on it in three ways only: promote a term that has earned its own keyword and ad, block a term you never want with a negative, or leave it alone and note why. That routine is search term mining, and it is what keeps broad match honest.
Watch word patterns rather than individual strings. A word recurring across many poor terms deserves one negative; a word recurring across converting terms deserves a keyword. When a term reveals a question rather than a purchase, answer it with content instead of paying for the same click again. If you run Google Search campaigns, this is the report to open first.