People usually find data by following a link to it or by searching for it, whether through a web search engine or a more site specific search.
Linked data allows assigning URLs not just to datasets, but to specific bits of data within that dataset, making it easy to share pointers to data. It is easier to back up reports or charts by citing the data that supports it.
Because everything has a URL, assuming it is publicly accessible on the web, then web search engines like Google, Bing etc are able to index the data and direct users to it. In addition to their mainstream approach of indexing the text on web pages, they are increasingly making use of metadata embedded in web pages to influence search ranking and to enrich how search results are presented. This embedded metadata takes the form of linked data using the schema.org vocabulary.
So, in site-specific searches, it is possible to supplement text based indexes with a more structured search using metadata. Linked data is well suited to linking datasets to standards-based machine readable metadata, helping people find the data they want.
Filtering within a dataset on environment.data.gov.uk