You can search for assets by GUID or assets and templates by string. The given phrase will display results separately for template names and asset names (or GUID).
By default, search engine is set to "strict mode" for a specific GUID or keyword (e.g. template or asset full name). Although it also displays records that start or end with a given word, due to the way the names are sometimes written without spaces. You can switch to an "non-strict search" (e.g. by typing part of the GUID or any part of the name), but this can give a large number of results and taking a long time to load them.
The second search box is for searching texts by GUID or phrase, in the selected or all languages. You can use the strict / non-strict mode by checking the checkbox next to the asset search field.
See the FAQ section for more information.