Perhaps you should try some spelling variations:
"online models" » "online model", "line models", "online mode", "online modells", "online modelsls", "ononline models"
"linear mode" » "linear model", "linear models", "bilinear model"
"line mode" » "line model", "line models", "online mode"

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: (((("line mode") OR ("linear mode"))) OR ("online models")).
• Removing quotes may allow a broader search: (((( line mode ) or ( linear mode ))) or ( online models )).
• Adding a wildcard symbol may retrieve word variants: (((("line mode") or ("linear mode"))) or ("online models"))*.