Google SERP result works on various factors, it will show query related page according to user search query & behaviour.
For Example: In your location most of the user search for “Buy Wrist Watches” & they click most of the time to Man`s related watch pages or they spend most of the time in Mans Watch Webpages. Then Google will index the pages according to user preferences & behaviour.
But still if you want to index your home page in the search query then I suggest you to use your home page for “Buy Wrist Watches” keywords in link building.