There is a lack of knowledge about the tax system.

大家对税制缺乏了解。

《牛津词典》

Atheism is an effect of that knowledge, not a lack of knowledge.

无神论就是学习知识的结果，而不是因为无知。

youdao

However, at lower levels there is (a lack of knowledge) of the issue.

然而，从低一点的层面讲，这还是一个有待考虑的问题。

youdao

Also,there is a widespread lack of knowledge among local health workers about how to use antivenoms.

VOA: special.2010.01.25

to express a lack of complete knowledge about the multitude of subjects.

它可以用来表达你对一些话题并不完全了解。

I don't know 课堂 - SpeakingMax英语口语达人

but also very non-affrontively, express a lack of complete knowledge

又不冒犯地表达对某事不完全清楚，

I don't know 课堂 - SpeakingMax英语口语达人

They attack what they see as a lack of knowledge and respect for their own cultural and social norms.

ECONOMIST: Islam in the Netherlands

In the article, there was mention of a lack of knowledge on a series where the series has remained single-player.

FORBES: Single Player Matters: Why Not All Games Need to Be 'Social'

Police in the area have reported a lack of knowledge and complacency among local businesses regarding proper procedures for serving alcohol.

WHITEHOUSE: Residents and Businesses Unite to Reduce Substance Abuse in Chicago��s Chinatown | The White House