What do we know about Jamie Foxx and Katie Holmes's relationship? Very little, to be honest. (Sorry.)

The couple is famously private, but what small glimpses they allow into their lives seem to be full of nothing but love. So predictably, Foxx has good advice to give in the dating department.

Jamie Foxx and Katie Holmes lead
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Foxx's friend Olivia Munn learned a lot from Foxx, and she passed on his insight while being interviewed by E!'s Busy Tonight. At one point, Munn was struggling in the romance department with an unnamed actor, and while she called them "official," the mystery beau didn't. Understandably, she was hurt.

"I'm on one side of this party and he's on the other side, talking to different girls and stuff, and I'm feeling so depressed," she said. "I decided to leave early, and then Jamie stops me and he's like, 'Where are you going?'"

Jamie Foxx and Olivia Munn embed
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It didn't take Foxx long to figure out what was going on. "Is he the reason you're leaving?" Munn recalled him asking. That didn't stop her though — she left the party, but Foxx still checked in.

"He's like, 'Go home. I'm going to call you later — and if you don't pick up, I'm going to leave you a voicemail!'" Munn said. "The next morning, I got a call from Jamie. He left a voicemail and said, 'Did you come out here to be somebody's girlfriend? No! Did you come out here to be somebody's wife? No! Did you come out here just to date this guy? No! Did you come out here to be an actress? Yes! Don't you ever, let me see you cry about some guy like that ever again! Don't you ever let some other guy make you feel like that ever again!'"

"It was so sweet. He was just so earnest. He was like, 'I never want to see you let any man make you feel that small again," she said. "Every now and then, [his message] would pop into my head — and, of course, it kind of veered off sometimes — but I'll think about that sometimes, and it brings me back to center."

No wonder Jamie and Katie seem so happy — he's basically a romance guru.