If you are using the word find citations/insert citation dialogue box - there are no parameters to set, it is a generic seach for any word match. In fact if you wanted the author “Li” it would bring up that letter combination in pretty much every field in every record. I massively dislike that dialogue and only remember it is an option, when someone complains about its non-functionality.
To get any control, it is much better to jump to endnote and use the more powerful seach there and insert the citation into word (copy/paste shortcuts work, or the Alt+2 (on a PC) command once it is selected.