This paper describes the interaction among language resources for an adequate concept annotation of domain texts in several languages. The architecture includes domain ontology, domain texts, language specific lexicons, regular grammars and disambiguation rules. Ontology plays a central role in the architecture. We assume that it represents the meaning of the terms in the lexicons. Thus, the lexicons for the languages of the project (http://www.lt4el.eu/ - the LT4eL (Language Technology for eLearning) project is supported by the European Community under the Information Society and Media Directorate, Learning and Cultural Heritage Unit.) are constructed on the base of the ontology. The grammars and disambiguation rules facilitate the annotation of the text with concepts from the ontology. The established in this way relation between ontology and text supports different searches for content in the annotated documents. This is considered the preparatory phase for the integration of a semantic search facility in Learning Management Systems. The implementation and performance of this search are discussed in the context of related work as well as other types of searches. Also the results from some preliminary steps towards evaluation of the concept-based and text-based search are presented.