Perhaps you should try some spelling variations:
"online chat research experiments" » "online chat research experimental", "online chat research experience", "online chat research experiences", "online what research experiments", "online chain research experiments", "online wheat research experiments", "online chapter research experiments"
"online lin research documents" » "online lin research arguments", "online lin research comments", "online lin research catchments", "online line research documents", "online link research documents", "online lan research documents", "online li research documents", "online linux research documents"
"online lin search document" » "online link search document", "online li search document", "online linux search document", "online line search document", "online levin search document"

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: (((("online lin research documents") OR ("online lin search document"))) OR ("online chat research experiments")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"online lin research documents\") OR (\"online lin search document\"))) or (\"online chat research experiments\"))".
• Removing quotes may allow a broader search: (((( online lin research documents ) OR ( online lin search document ))) or ( online chat research experiments )).
• Adding a wildcard symbol may retrieve word variants: (((("online lin research documents") OR ("online lin search document"))) or ("online chat research experiments"))*.