đã lâu lắm rồi 
it has been a long time since [ đã ] : (past tense marker); first; after, following
[ lâu ] : long (of time); to take a long time
[ lắm ] : very, quite
[ rồi ] : already, then, after that, afterwards, next
Most Common Compounds Set 1:
Most Common Compounds Set 2 :