how to find particular sentence only using AEM site search?

Hi @keeleyjo,

Search icon in top tool bar is used for search function within AEM instance.

In this case, as the requirement is to bring the pages of matching search sentence, you can be in "Sites" console and then search using the same top toolbar, you will be able to see the page card coming up in the search results provided you have similar sentence in the page content or in the page description field.

Using Filter in the left section, you can narrow down the search further. 

Since the question is tagged with AEM 6.1, below is the respective documentation for further detailed information. 

https://docs.adobe.com/content/docs/en/aem/6-1/author/author-environment/search.html

Behind the scene:

This is executed as a full text search query, you can enable logger in your local instance -> perform search -> observe the logs.

Sample screenshot for reference from 6.5.0 : (Have authored similar sentence in both description field and in page content, it is able to bring up the result)

This can be achieved through omni search functionality https://docs.adobe.com/content/help/en/experience-manager-learn/sites/developing/search-tutorial-develop.html.

You can do a full text search in AEM sites console like "how to buy a t-shirt" enclosed in a double quotes. See https://helpx.adobe.com/in/experience-manager/6-3/assets/using/gql-search.html for more details.