Meta tags help search engines to better index your pages. Every search engine uses meta tags differently so it is best to use all of the below tags even though we are specifically interested in the keywords tag here.
If you look at the top part of your HTML code you will see something like the following. (You may have to add the Meta Tags yourself if you did not already add them.
<TITLE>Page Title Here</Title>
<META name="resource-type" content="document">
<META name="description" content="a short description of your page goes here">
<META name="keywords" content="some_keyword, another_keyword, yet_another_keyword">
<META name="distribution" content="global">
See the one that has the keywords? Add XaTuring and Xa-Turing (alternate spelling) to the list of keywords.
<META name="keywords" content="some_keyword, XaTuring, Xa-Turing, another_keyword, yet_another_keyword">
These tags are useful in general when making web pages of any kind. More information on Meta Tags can be found by clicking here