over的使用方法

Normally, Americans do not assess their visitors in such relaxed surroundings over prolonged small talk; much less do they take them out for dinner, or around on the golf course while they develop a sense of trust and rapport. Rapport to most of us is less important than performance.

over的使用方法教程上说是当....时的意思，但我如何感觉是通过....渠道办法的意思？

教程的说法是对的。over 表示 during 之意。

If something happensovera particular period of time oroversomething such as a meal, it happens during that time or during the meal. 在…期间

They had a chat over their lunch. 他们吃午饭期间聊天。（边吃边聊）

翻译成通过，事实上是经过，经过表示过程，过程表示时间。如此理解就好懂了。