cards such as BLS where it says can only be specail summ by removing one light and dark monster from play. If these cards are in the grave yard can you remove those monster again and bring the card onto the field??

No you cannot... that sentence ONLY applies while they are in your HAND.

As said many, many times before...

Unless it an effect SPECIFICALLY states you can Special Summon them from the Graveyard (ex. Knight's Title, Bonding H2O, etc), the Special Summoning MUST be from your hand and nowhere else.