Good, but not great, earnings and some looming bumps in the road have investors worried.Shares of Toyota Motor (TM -6.44%) fell on Thursday after the company reported earnings, on concerns about a scandal in Japan and softening demand in China.As of 11:30 a.m. ET, Toyota's American depositary shares were down about 5.6% from Wednesday's closing price. Earnings were good, but there are reasons for concernToyota's earnings weren't bad. The Japanese auto giant reported operating profit of 1.3 trillion yen ($8. ...