Perhaps you should try some spelling variations:
earnings find » earnings from, earnings gain
learning rate » learning rates, learning gated, learning rapid
among forest » among first, among foreign, among formal
chang lost » change cost, changed post
wang yang » wang yan, wang liang, wang yanling
di chang » ii chang, yi chang, jin chang

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: wang yang di chang lost ((earnings find) OR (learning rate)) among forest ;~.
• Adding a wildcard symbol may retrieve word variants: wang yang di chang lost ((earnings find) or (learning rate)) among forest ;*.