Search volume that Google provides is tricky in many ways. In particular, starting from the year 2016, Keyword Planner shows “combined search volumes” for groups of similar keywords. To illustrate this, if you want to get separate search volume for “seo”, “search engine optimization” and “search engine optimisation” with the British spelling, you can’t do that.
Here’s what the Keyword Planner will show.
Accordingly, as Google Keywords Data API in DataForSEO is based on Google Ads, we can only return you the values that the data source provides. Unfortunately, there is no opportunity to define a broad, exact, or phrase match when setting tasks to the Google Search Volume endpoint in DataForSEO API.
However, as a workaround, you can go with one of the following approaches:
1 Submit similar keywords in different requests to get their search volume.
Such keywords are often grouped together, so we recommend submitting them into the "keywords" arrays of separate POST requests.
2 Use the Keyword Suggestions endpoint in DataForSEO Labs API.
Here, you can set the "exact_match" parameter to true to obtain terms that will include the exact keyword phrase you specified. With every keyword suggestion, you will get its search volume rate for the last month, search volume trend for the previous 12 months, as well as current cost-per-click and competition values. On top of that, the Keyword Suggestions endpoint will supply you with the minimum, maximum and average values of daily impressions, clicks, and CPC for each result.
3 Use the Keyword Ideas endpoint in DataForSEO Labs API.
When you set a task to this endpoint, you can set the parameter "closely_variants" to true for getting results based on the phrase-match search algorithm. Conversely, if you set this parameter to false (default value), the results will be based on the broad-match search algorithm. Each keyword idea in the results comes with search volume and other essential keyword metrics. Besides that, you will get impressions, clicks, and CPC data.