Along with the development of the dataādriven research paradigm, there are exponentially increasing datasets, which bring challenges to researchers in the efficient retrieval of relevant datasets. Previous studies mainly focused on query expansion methods based on sparse retrieval models to improve the accuracy and recall in retrieval. We investigated the use of semantically rich information to retrieve relevant datasets and the benefits of using domaināspecific dense vector representation as opposed to general representation. First, we used pairs of metadata fields that have semantic relevance to construct the domaināspecific weakly supervised training data. Then, a preātrained transformerābased deep learning model is fineātuned on the training data using the contrastive learning method. Finally, dense vector representations of the queries and datasets are obtained based on the fineātuned model. The relevance of a dataset to a query is measured by the similarity between the vectors. To evaluate the performance of the proposed model, we collected 104,683 datasets from 13 research data repositories, recruited volunteers to design researchāoriented queries, and annotated the retrieval results. The experimental results show that compared with the domaināindependent fineātuned model, our proposed method can improve the NDCG@10 score by about 5%.