Keyword Research
November 21st 2019

Keyword Research and The Search Volume Illusion

7 min read

Although there are many keyword research tools available, they all take a similar approach. No matter what tool you use, the method tends to be the same.

An initial search term is input so that the tool can generate a list of keyword ideas. At some point in the process, that list gets filtered based on certain criteria, one of which is always monthly search volume.

But this keyword research process is flawed.

There is a mistaken assumption that keyword phrases with little search volume have correspondingly low value. That’s based on the belief that pages targeting those search terms will get very little traffic. 

But nothing could be further from the truth. 

Eliminate these search terms from your keyword list, and you remove the ability to rank for a large number of search queries.

Content in the Post-Hummingbird World

To understand how Google analyzes and ranks content today, we have to consider three major updates to its core algorithm.


In response to rampant keyword manipulation by SEOs, Google introduced an algorithm update known as Hummingbird. Hummingbird signaled a change in Google’s index from a collection of keyword terms to a group of entities (people, places, things, dates, etc.).

Quality Update

Poor quality sites, relying heavily on search engine optimization, continued to rank well. Google responded by increasing the importance of key site quality signals in its rankings. 


RankBrain is a machine learning engine designed to interpret users’ search intent and serve the most relevant results. It improved the way Google understands the relationships between entities so that it can relate concepts that aren’t explicitly mentioned in a piece of content.

The Topic Layer

On September 24, 2018, Google announced the addition of a topic layer to their Knowledge Graph. Many marketers still do not understand the implication of the topic layer. 

Google uses topic models to sort and prioritize the 130+ trillion web pages. Google’s topic layer analyzes all the content for a given topic, identifying hundreds or thousands of subtopics and their relational patterns. 

The aim of the topic layer is that Google wants to tailor its results to potential search intent profiles based on someone searching for a particular topic. With the Topic Layer, Google’s engineers are trying to provide semantically related concepts that help get searchers to the next step in their search journey. 

It can be considered an automatic topic outline that dynamically changes depending on the search term.

What does this mean for content?

Google’s evolution, away from being a keyword-focused search engine and toward a semantic and topic-focused engine, means that the traditional ways of thinking about how to prioritize content are no longer as useful or relevant.

Most content strategists use metrics like Monthly Search Volume, Keyword Difficulty (which measures competition), and Domain Authority to gauge which content ideas are important and worth pursuing. The first metric, in particular, remains a major data point for content decisions.

The problem with this approach is that most sources of MSV data provide only the keywords that get trackable search volume, which out of the billions of searches that happen every day, is fewer than 10% of everything people are searching for. 

Keywords and their associated volumes will never be a reliable roadmap to what it means to be “about” a topic, nor will they tell you the true potential of a piece of content. An authoritative piece of content on an authoritative domain can get significant organic traffic, even from low-volume keywords. 

This is where MarketMuse comes in. 

The Term Pool Multiplier

The term pool multiplier is the volume potential of a piece of content beyond the trackable volume of ranking keywords. It’s the organic search traffic a page gets from untrackable variant keywords (the term pool) it also ranks for, in addition to the totality of low-volume terms that add up to significant traffic.

90% of search volume comes from phrases with fewer than ten searches per month.

Why the Term Pool Multiplier Matters

Trackable volume that can be attributed to a single keyword is only a tiny fraction of what can be expected for page performance. 

Authoritative content will often rank for hundreds, if not thousands, of variant and related keywords. All of these queries can drive organic traffic to a page, even if the page isn’t explicitly about it. Thus, calculating the traffic volume potential for a single keyword does not take into account the full traffic potential of the content.

Take, for example, the search term “how to buy a grill.” Only 110 people are searching for this topic per month.

SERP for the search term "how to buy a grill".

However, this page manages to pull in over 3,000 visits per month thanks to its ranking for over 1,000 keywords.

Screenshot showing keywords, traffic, and traffic cost for a web page.

Notice how the iterations of the head term yield relatively low volumes as well.

Organic search position for the page

Here’s another example for the search term “bar stool buying guide.” 

SERP overview for the search query "bar stool buying guide".

Notice how the competitive cohort in the SERP shows that the links ranking for this term have a sizeable term pool multiplier – bringing their overall volume up.

Are you not convinced yet? Here are some more low-volume keyword examples that generate significant traffic.

Building the Cluster Impacts the Term Pool Multiplier

Some content topics are considered to be competitive keywords. But despite having low MSV, support the cluster by raising the authority of the entire cluster.

By creating an integrated cluster of content that attends to all searcher intents, the “net” with which you can catch the term pool multipliers (and associated volume) is more extensive. From the perspective of the customer, you are adding content that services key user intents in the buyer’s journey. This allows people to contextualize their search for what they need and helps them make the right purchasing decision.

Authority Drives Organic Traffic

Google ranks content based on the “EAT” framework: Expertise, Authority, and Trust

This is how Google not only evaluates individual pieces of content but domains as a whole. By creating lots of content that demonstrate expertise and authority, and by being a trusted source of information, you will find your content prioritized on the topics within your EAT wheelhouse.


While Google has advanced, search engine optimization has not. The keyword research process, in particular, is still stuck with an outdated one-page-one-keyword approach. It’s time content marketing caught up with search engines.

Written by Camden Gaspar camden_gaspar