Perhaps you should try some spelling variations:
"math skills surveys." » "math skills survey.", "math soil surveys.", "motor skills surveys."
"math school surveys." » "math school survey.", "map school surveys.", "small school surveys.", "smart school surveys."
"small schools survey." » "small school survey."
"small schools serve." » "small school service.", "small school survey."
"math site surveys." » "math firm surveys."
"math social surveys." » "cash social surveys.", "data social surveys.", "health social surveys."

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (("math skills surveys.") OR ((((((("math school surveys.") OR ("math social surveys."))) OR ("math site surveys."))) OR ((("small schools survey.") OR ("small schools serve."))))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"math skills surveys.\") or (((((((\"math school surveys.\") or (\"math social surveys.\"))) or (\"math site surveys.\"))) or (((\"small schools survey.\") OR (\"small schools serve.\"))))))~".
• Removing quotes may allow a broader search: (( math skills surveys. ) or ((((((( math school surveys. ) or ( math social surveys. ))) or ( math site surveys. ))) or ((( small schools survey. ) OR ( small schools serve. ))))))~.
• Adding a wildcard symbol may retrieve word variants: (("math skills surveys.") or ((((((("math school surveys.") or ("math social surveys."))) or ("math site surveys."))) or ((("small schools survey.") OR ("small schools serve."))))))*.