Perhaps you should try some spelling variations:
"value h2o ratio" » "value o ratio", "value h2o reaction", "value 2 ratio", "value 12 ratio", "value 32 ratio"
"value how ratio" » "value how ratios", "value how radio", "value low ratio"
"value co ratio" » "value co ratios", "value o ratio", "value 2 ratio"

Try widening your search to All Fields.

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: (("value co ratio") OR ((("value h2o ratio") OR ("value how ratio")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"value co ratio\") or (((\"value h2o ratio\") OR (\"value how ratio\"))))".
• Removing quotes may allow a broader search: (( value co ratio ) or ((( value h2o ratio ) OR ( value how ratio )))).
• Adding a wildcard symbol may retrieve word variants: (("value co ratio") or ((("value h2o ratio") OR ("value how ratio"))))*.