If you’ve been running Google Performance Max (PMax) campaigns, you know the promise: AI takes the wheel, optimising your ads across Search, YouTube, Display, Maps, and more. But with great automation comes the worry—is the AI really understanding your business the way you want it to?
That’s where Search Themes come in. Think of them as gentle guidance for Google’s AI, helping it find the right search traffic without tying its hands. They’re not a strict targeting tool, but a way to steer the AI toward searches that matter most to your business.
What Are Search Themes, Really?
At its core, a search theme is just a set of words or phrases that give the AI more context about your products or services. Unlike Search Term Insights, which simply reports what people are actually searching for, search themes are proactive signals. They fill in the gaps where your landing pages, product feeds, or creatives might not tell the whole story—especially for new products, niche offerings, or specific promotions.
By adding these extra clues, you’re helping PMax campaigns reach users who might otherwise slip through the cracks. It’s like giving a GPS some extra directions so it doesn’t miss a hidden turn.
How Search Themes Work
Advertisers can add up to 50 words or phrases per asset group, giving the AI plenty of material to work with. These themes operate much like phrase match or broad match keywords in standard Search campaigns. One thing to remember: if you have an exact match keyword in a standard Search campaign, it will always take priority over a PMax search theme for the same query. This keeps your top-performing search terms safe while letting PMax do the heavy lifting elsewhere.
To make things easier, Google also provides a “search theme usefulness indicator”. Alongside the Search Term Insights report, this helps you see whether your themes are actually driving new traffic or just overlapping with searches the AI would have found anyway.
Why It Matters
Search themes aren’t just a nice-to-have—they’re a way to add strategic control to an automated system. They’re perfect for:
- Launching a new product or service
- Capturing traffic in a niche market
- Highlighting a specific promotion or seasonal campaign
Basically, if you have traffic you want to reach but the AI might not “get” on its own, search themes are your friend.
Best Practices for Search Themes
To make the most of this feature:
- Add Incremental Value: Don’t just repeat what your landing page already says. Pick words and phrases that bring new insight to the AI.
- Align With Your Goals: Focus on the searches that matter to your current campaigns—new markets, new products, or special promotions.
- Watch Out for Cannibalisation: Make sure your top-performing keywords are set as exact match in standard Search campaigns. This prevents your campaigns from competing with themselves.
- Keep Learning: Use the Search Term Insights report regularly. Check the “usefulness” indicator and see which themes are actually driving results. Update and refine your themes over time.
Bottom Line
PMax campaigns give you the convenience of full automation, but search themes let you guide the AI with purpose. They’re a simple way to make sure your new products, niche offerings, and specific promotions get the attention they deserve. When used thoughtfully, search themes can help your campaigns work smarter—capturing traffic you might otherwise miss.
Want Your PMax Campaigns to Work Harder?
Search themes are a small addition that can make a big difference. At Digital 38, we help brands build the right strategy to get the best results from Performance Max. Reach out to see how we can help your campaigns capture the right traffic at the right time.
