Your idea is quite right. It is appropriate to express gratitude to others for their help, but it is wise to consider the feelings of those who have not helped. Colleagues in a unit really need to think more, otherwise, because a good thing has no intention of letting others have opinions, it will be a bit of a loss.

In this case, your original intention is nothing more than to thank those colleagues who have helped you, and the help of colleagues is actually a voluntary act without asking for anything in return. Therefore, it is really unnecessary and inappropriate to eat and buy gifts.

The best way is that you can buy some snacks to eat, such as candy, melon seeds and fruits, which are beautiful and delicious, and not stingy or deliberate. Carefully select a big bag in the supermarket and put it on everyone's desk at will. The atmosphere is easy-going and lively, helping but not helping, familiar and unfamiliar, and everyone has a share. It's very tasty when you meet it, and it's definitely a good choice to earn popularity and express your mood when you don't meet it.

In any case, this way of thanking is natural and sincere. As long as it is handled properly under the guidance of this principle and thought, everyone will be happy.