Well, get set for a shock. Access won't make a single word bold or italic in a report unless it is in a control of its own. (In which case it would be a simple change of the control's font properties.)
Access is NOT a word-processing package. Nor is it a presentation package. The side effect of these two NOTs is that it is NOT going to provide individualized text formatting on its own. That's not what it is for. When formatting an OBJECT (note: Not "when formatting a word"), you can apply a uniform format to the text of the object if it is a text object. That is the limit for straight Access.
Now, having said that, there are ways to do it with a little bit of cheating, but you need to know EXACTLY which printer you are going to print this report on, and if you change printers, you are screwed. You could force certain control or escape sequences into the text field of your object to surround a particular word with the control sequences for bold or italic print. BUT it won't display right, because (again), Access is NOT a WYSIWYG editing package.