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: "who discovered all living things are made of cells?" whose answer is Matthias Jakob Schleiden.
Each document should contain about 30 words, and these documents should contain useful information.

Query: who proposed cell theory
Useful Output:

Doc 1: A cell is a basic unit of life, and it is considered a structural and functional unit of an organism. Robert Hooke (1665) discovered the cell.
Doc 2: The classical cell theory was proposed in 1839 by Theodor Schwann and comprises three main tenets. First, all living things are composed of
Doc 3: Cell theory was originally given by German botanist Matthias Schleiden & German physiologist Theodor Schwann together based on their researches
Doc 4: In 1839, M.J. Schleiden and T. Schwann proposed the cell theory. This was further expanded by Virchow in 1858. The main features of the cell
Doc 5: Matthias Schleiden and Theodor Schwann proposed the cell theory in 1838, stating that all living organisms are composed of cells, which are the