Books and magazines are filled with the hows and whys, the rights and wrongs of buying and selling, of manufacturing and shipping, of finance and management.

书籍和杂志写满了如何和为什么，写满了关于买卖的正确与错误，写满了生产和运输、金融和管理。

youdao

We started buying and selling books nine years ago when we were both working day jobs.

FORBES: Entrepreneurial Life: Tales of a Young Bookseller

At age 10 he started buying books and other "low-end stuff" at garage sales and re-selling it on eBay.

FORBES: Magazine Article