For certain and Without any elaboration

For certain adverb - Definitely or positively (`sure' is sometimes used informally for `surely').

Without any elaboration and for certain are semantically related. In some cases you can use "Without any elaboration" instead an adverb phrase "For certain".

For certain and without any elaboration are semantically related. Sometimes you can use "For certain" instead an adverb phrase "Without any elaboration".