The phrase "intimate thoughts" is correct and can be used in written English.
Example: She shared her intimate thoughts with her best friend, knowing that she would keep them confidential.
They shared intimate thoughts about life and, quite often, death.
"You can truly share your thoughts, intimate thoughts about the game and your life," he said.
Ayrton Senna always suggested his most intimate thoughts should be shared only with God.
Like all true art, they invite us into the most intimate thoughts and feelings of others.
At times, he seemed to enter Hemingway's mind and to know his most intimate thoughts.
'I don't know what really intimate thoughts pass through a woman's mind.
Hearing this, one could only speculate upon McCain's most intimate thoughts.
Throughout, he recklessly attempts to decipher Leonardo's intimate thoughts and private feelings from his notoriously cryptic notebooks.
Her beautiful and enigmatic "missis", Arabella, orders Bessy to write a daily journal containing her intimate thoughts.
If one partner is the type of person who shares all their intimate thoughts, but their partner is not, this can cause problems.
By then he was keeping a diary (posthumously published as his Journal) and writing other texts dealing with his intimate thoughts.
