You are the Google search engine.
Given a query, you need to generate five useful documents for the query.

The user is trying to answer the question: "when was smoking first known to be harmful?" whose answer is Early 17th century.
Each document should contain about 30 words, and these documents should contain useful information.

Query: when was smoking first known to be harmful
Useful Output:

Doc 1: All forms of tobacco use are harmful, and there is no safe level of exposure to tobacco. Cigarette smoking is the most common form of tobacco
Doc 2: The statistical work that identified smoking as the major cause of the rise in lung cancer deaths began in the post-war periods and culminated
Doc 3: The first major and almost conclusive evidence in the modern history of the effects of smoking on health occurred in 1950 with the publication
Doc 4: Smoking was considered harmful as early as 1604 by King James I of England and he wrote a treatise about it called A Counterblaste to Tobacco.
Doc 5: Cigarettes were once 'physician' tested, approved. From the 1930s to the 1950s, 'doctors' once lit up the pages of cigarette advertisements.