We designed CROEQS, which allows users to search a multimedia database. The query formulation is not only based on text, but also on higher-level attributes: users can query videos about persons based on additional information about that person. The aim of CROEQS is to build a more efficient search engine, able to respond to queries on a higher level. To this end it makes use of an ontology in which the domain knowledge on people fulfilling a role during a temporal interval in general, and politicians holding a political office specifically. In this paper, we focus on the impact of the semantic clause on the result set size. The evaluation results demonstrate a significant impact, which can be used for targeted search, and show that temporal information is useful if the period during which a the temporal statement holds is limited.