Perhaps you should try some spelling variations:
"endogenous estrogens sulfide" » "endogenous oestrogens sulfide", "exogenous estrogens sulfide", "endogenous pyrogens sulfide", "exogenous estrogenss sulfide", "endogenous hydrogens sulfide", "endogenous nitrogen sulfide", "endogenous hydrogen sulfide"
"endogenous estrogen sulfide" » "exogenous estrogens sulfide", "endogenous hydrogen sulfide", "endogenous pyrogen sulfide", "endogenous nitrogen sulfide", "endogenous dinitrogen sulfide"
"exogenous estrogen sulfide" » "exogenous estrogens sulfide", "exogenous nitrogen sulfide", "exogenous hydrogen sulfide", "exogenous dinitrogen sulfide"

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: (((("endogenous estrogen sulfide") OR ("endogenous estrogens sulfide"))) OR ("exogenous estrogen sulfide")).
• Removing quotes may allow a broader search: (((( endogenous estrogen sulfide ) or ( endogenous estrogens sulfide ))) or ( exogenous estrogen sulfide )).
• Adding a wildcard symbol may retrieve word variants: (((("endogenous estrogen sulfide") or ("endogenous estrogens sulfide"))) or ("exogenous estrogen sulfide"))*.