Technical Guidelines for Digital Double Water Network Construction (Trial) may be a document issued by China Ministry of Water Resources or relevant departments. To obtain this document, you can try the following methods:

1. Government official website: Visit the official website of the Ministry of Water Resources of China or relevant government departments to find their legal and policy files. Usually, government departments will provide free download or online access options on their websites.

2. Academic databases: Some academic databases and online libraries may provide download or citation links of government documents. You can try to access these resources, such as the National Library of China, China HowNet, and the full-text database of China academic journals.

3. Contact relevant departments: If you can't find this document online, you can try to contact the Information Office of China Ministry of Water Resources or relevant government departments and ask them how to obtain a copy of this document.

Please note that the availability of government documents may be restricted by laws and policies, so legal access may be required.