Miley Cyrus: Buys New Pad ... For Private Time With Liam

Miley Cyrus dropped major cash to buy a Malibu home, right next to Liam Hemsworth ... which doesn't mean she's moving out of his place -- it actually looks like they're expanding.

Reports surfaced Thursday that Miley's new pad signaled a split, but we've learned it's the exact opposite. The house is officially 0.2 miles from Liam's, but in reality their driveways actually butt up against each other.

Our sources tell us Miley's new place will be her primary address ... with most of her stuff, including her bed. But the real reason for the purchase -- QT with Liam.

We're told Liam's 3 bedroom home has become overcrowded with guests -- Liam has a bunch of Aussie buddies who've been crashing there. Throw in Miley and her 5 dogs and things get messy.