Correct

私房话

/ sī fáng huà /
Strokes
https://i.cchatty2.com/filters:format(webp)/fit-in/684x0/img/202102/私房话-Chinese-idioms-Cchatty-afde442f-e735-48e6-9907-1d1ff90921a0-1612777879.jpg

Collocation

1
不应偷听人家的
2
没完没了的私房话
3
讲私房话
4
说私房话

Definition

私房话

Literally means:

speaking only in their own room

Actually means:

私房, confidential or restricted to family members.

This phrase refers to words that are restricted between the couple or bosom friends and are kept from others. It usually refers to words that are exchanged between family members, couples, bosom friends or classmates.

私房,范围局限在自家人之间的,或只在夫妻之间说的话,或只在关系密切的人之间说的,不让其他人知道的话。多指家人,夫妻或亲密的朋友、同学之间的话。

Example

Used as object. (作宾语)
1
men
他们
夫妻
de
fánghuà
私房话
shì
men
他们
de
yǐn
隐私
  
,
zěnme
怎么
可以
tōutīng
偷听
ne
  
?

Their husband and wife's private talk is their privacy, how can you eavesdrop?

2
Rénjiā
人家
xiǎoniáng
小姑娘
shuō
de
shì
fánghuà
私房话
  
,
shì
men
她们
háizi
女孩子
de
shì
  
,
nánrén
男人
shì
néng
tīng
de
  

People's little girls are talking about private rooms, is their girl's business, you a big man can not listen to.

3
men
他们
liǎng
shì
duōnián
多年
de
hǎo
péngyou
朋友
  
,
guǎn
不管
zài
一起
de
shíjiān
时间
shì
cháng
shì
duǎn
  
,
zǒng
yǒu
méiwánméile
没完没了
de
fánghuà
私房话
  

The two of them have been good friends for many years, whether the time together is long or short, there is always endless private talk.