Perhaps you should try some spelling variations:
"human leases periodicals." » "human senses periodicals.", "human diseases periodicals.", "human measures periodicals.", "humans leaves periodicals.", "human losses periodicals."
"human genes periodicals." » "human genomes periodicals.", "human bees periodicals.", "human games periodicals.", "human gene periodicals.", "human genetics periodicals.", "human genetic periodicals."
"human ages periodicals." » "human agents periodicals.", "human bees periodicals.", "human changes periodicals.", "human age periodicals.", "human images periodicals."

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("human genes periodicals.") or ((("human ages periodicals.") or ("human leases periodicals."))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("human genes periodicals.") OR ((("human ages periodicals.") OR ("human leases periodicals."))))*.
• Removing quotes may allow a broader search: (( human genes periodicals. ) or ((( human ages periodicals. ) or ( human leases periodicals. ))))*.