The Dutchman believes that despite a few poor results, they are improving in their performances.
He also singled out captain Bruno Fernandes for praise, stating the Portuguese would soon be back to his best.
He told reporters: "I think he is capable and he has proven (himself) already so many times in the Premier League. He can create many chances. I am convinced he will not do differently.
“He will find his form. He is already creating chances but he will make final passes, he will score goals. 100 per cent and it is just a matter of time."
On their improvement, he added: "I think you have to assess the situation. Still now we are working and we are in progress. We have to sign players and we made the choice to sign very young players. Like last year, Hojlund and Zirkzee and Leny Yoro are players we believe in for this moment but also for the future and we have to build them.
“When I started we spoke about more, we had to make a switch in the dressing room. We have turned a corner and we have to work with the squad and that takes time and of course, (that is) also not good behavior for me, I am impatient. I want to go straight forward. To be fair, we have also had success in the last two seasons and we have to work very hard to bring further success."