Below are some resources, both books and on the web for discerning your vocation.

The Constitutions of the Nuns of the Order of Preachers

Vultum Dei Quaerere Apostolic Constitution on Women's Contemplative Life, Pope Francis 

Sponsa Verbi, by Bl. Dom Marmion, OSB. Short book on the beauty and obligations of the contemplative life. (PDF file)

Paths of Love by Joseph Bolin
Website with many resources by Joseph Bolin

The Spirit of St. Dominic by Fr. Fabio Giardini, OP

To Heaven with Diana, the letters of Bl. Jordan of Saxony, successor of St. Dominic, to Bl. Diana d’Andalo, OP, one of the first nuns of the Order of Preachers

Saint Dominic: the Grace of the Word by Fr. Guy Bedouelle, OP

The Challenge of the Dominican Contemplative Vocation by Sr. Breda, OP