Its a love/ romantic song, though the question was asked 6 months back, iam answering it, just in case Teri Meri, Meri teri prem kahani hai mushkil (Your Mine, Mine yours Love Story is difficult/not possible) - Direct translation Meaning : Our Lover= Story is too complex/difficult Do Lafzon main yeh bayan na ho paye (Cannot be told in two words) In a single line : Our story is not so simple that it can be told in two words. Two words is derived from hindi word for love called PREM(love) thats the basis for using the two words(do lafz) This song has a combination of hindi and urdu words, like lafz is urdu for words. I hope this answers your question