Here are four considerations if you want to drive more conversions from voice search:

• Understand What Makes Voice Search Different: Voice search queries tend to be longer. In 2004, most searches were two or three words. Ten years later, search queries could be 27 or more words. Voice searches also tend to be more specific (for example, searching for “find the closest store that sells men’s black leather cowboy boots” instead of just “cowboy boots”).
• Analyze Your Longer Tail Keywords to Find Patterns: Since voice searches are usually more natural and conversational, keyword optimization should fit this new long tail landscape. Test variations on how people would naturally explain their needs in a query.
• Use Modified Broad Match Keywords: Modified broad match lets you specify that specific broad match keywords or close variants (such as + pizza + Chicago + delivery) must appear to show your search ad. So even if the voice search is 30 words, as long as three of those are “pizza,” “Chicago,” and “delivery” your ad will appear.
• Negative Out Keywords That Aren’t Driving Customers: As you test and refine your keyword list for voice search, be sure to negative any words from modified broad match that indicate the searcher is not a potential customer.