Search Keywords (Exact, Broad and Modified)
Dynamic Creative Ad Builder generates Exact and Broad match Keywords for your Ad Groups based on the categories from your product inventory on Step 3. Inventory and your Category Re-writes from Step 3.2 Edit Categories - Category Rewrites for Search Ads.
Ad Builder also makes use of Googles Broad Match Modifier (+) feature to ensure your ads will show for any permutation of the keywords within the search term.
Exact: Ads show on searches that match the exact term or are close variations of that exact term
Broad: Ads show on searches that include misspellings, synonyms, related searches and other relevant variations of this keyword.
Broad Match Modified: Ads show on searches where each +[keyword] was included in the search term in any order.
For more detailed definitions of Keyword matching see https://support.google.com/adwords/answer/2497836?hl=en-AU