Catalysis of the reaction: a thalianol = a thalian-diol. This reaction is the addition of a hydroxyl group to thalianol ((13R,14R,17E)-podioda-8,17,21-trien-3beta-ol) to create a thalian-diol ((13R,14R,17E)-podioda-8,17,21-trien-3beta,X-diol), where the hydroxyl group may be attached at one of several different available carbons in ring B or C of thalianol, indicated by the X.