Perhaps you should try some spelling variations:
communication foundation » communication education, communication communication, communication information
foundation methods » foundations methods, oxidation methods, validation methods
du lifei » lu yifei
du line » dual line, du livre
du lei » fu lei, mu lei
d line » 2d line, 3d line, d ling

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: communication foundation methods section ((((du line) OR (((du lifei) OR (du lei))))) OR (d line))~.
• Adding a wildcard symbol may retrieve word variants: communication foundation methods section ((((du line) or (((du lifei) or (du lei))))) or (d line))*.