Hello, Jamal. This can be done either with a find/replace action, in which you designate italics for the same words in the replace field (More/Font/Italics), or you can set up an Autotext entry that will always replace that phrase with an italicized one. If you're not familiar with Autotext, you can find it in Word Help or in a quick Web search for Word+Autotext.

Cordially,
Ulodesk