sharp practice
noun [ U ] uk/ˌʃɑːp ˈpræk.tɪs/ us/ˌʃɑːrp ˈpræk.tɪs/
（商业上的）不道德行为，不正当手段
a way of behaving, in business, that is dishonest but not illegal
The industry brought in rules to protect customers from sharp practice. 该行业制定了规章，旨在保护客户免受不正当手段的欺诈。