This paper shows that nondeterministic sensing semi-one-way simple k-head finite automata are more powerful than nondeterministic sensing one-way simple k-head finite automata for any k2, and sensing semi-one-way simple 2-head finite automata are more powerful than semi-one-way simple 2-head finite automata, which gives an affirmative answer and a partial solution to two open problems on sensing semi-one-way simple multi-head finite automata in Ref.[3].