When I book with VH, I ask for my room requests then, they are noted on my invoice.
Whether I will get them or not is another matter.
You should keep the request to no more than three things and put your main one first,
For example
Balcony room
Nice view
Close to pool.
I have only put one on ours in the hope I will get it. Which was nice view, as all rooms at the Yatch club have balconies.