KooSearch is the Huawei Cloud service specifically designed to provide enterprise-grade search capabilities with an out-of-the-box service model. Huawei Cloud describes KooSearch as a one-stop intelligent enterprise search solution built on Cloud Search Service (CSS). It enables organizations to construct enterprise search, knowledge retrieval, AI search, and document Q&A applications without having to independently build the underlying search infrastructure. The service integrates enterprise knowledge sources, search models, vector search capabilities, and other components required for enterprise information retrieval.

This directly corresponds to the question's description of an out-of-the-box search service designed for enterprise digitalization. Huawei's current KooSearch documentation explicitly emphasizes its ready-to-use enterprise search and RAG capabilities. KooPhone is associated with cloud-phone capabilities, KooMessage concerns enterprise messaging and communication, and KooMap provides map-related services; none is the dedicated enterprise search offering.

Therefore, KooSearch is the only technically valid choice. This aligns with the HCIA-Cloud Service domain covering Huawei Cloud platform and other value-added cloud services.

Reference topics: KooSearch Service Overview; Cloud Search Service; Huawei Cloud PaaS/aPaaS Services.

===============