Perhaps you should try some spelling variations:
"human tropics periodicals." » "human physics periodicals.", "human ethics periodicals.", "human economics periodicals.", "human trophies periodicals.", "humid tropics periodicals.", "humus tropics periodicals."
"human games periodicals." » "human gases periodicals.", "human ages periodicals.", "human homes periodicals.", "human gamers periodicals.", "human gametes periodicals.", "shuman james periodicals.", "human gazes periodicals.", "human genes periodicals.", "human gaits periodicals."
"human game periodicals." » "human flame periodicals.", "human care periodicals.", "human age periodicals.", "human gaze periodicals.", "human gene periodicals.", "human gait periodicals."

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("human tropics periodicals.") or ((("human games periodicals.") or ("human game periodicals."))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("human tropics periodicals.") OR ((("human games periodicals.") OR ("human game periodicals.")))).
• Removing quotes may allow a broader search: (( human tropics periodicals. ) or ((( human games periodicals. ) or ( human game periodicals. )))).
• Adding a wildcard symbol may retrieve word variants: (("human tropics periodicals.") or ((("human games periodicals.") or ("human game periodicals."))))*.