Perhaps you should try some spelling variations:
"carbamates chemistry metabolism" » "carbonates chemistry metabolism", "carabonates chemistry metabolism", "carbonate chemistry metabolism", "carbamates chemistry methods"
"global chemistry lectures" » "global chemistry structures", "global chemistry molecules", "global chemical lectures", "coal chemistry lectures", "cobalt chemistry lectures", "general chemistry lectures"

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: (("global chemistry lectures") OR ("carbamates chemistry metabolism")).
• Removing quotes may allow a broader search: (( global chemistry lectures ) or ( carbamates chemistry metabolism )).
• Adding a wildcard symbol may retrieve word variants: (("global chemistry lectures") or ("carbamates chemistry metabolism"))*.