Learn English – Fail trumpet onomatopoeia

Here are a few:

• Wheeze
• Huff
• Puff
• Pant
• Gasp

You might consider looking in the dictionary first:

poof 1 |po͞of, po͝of|(also pouf )
exclam.
1 used to convey the suddenness with which someone or something disappears: once you've used it, poof—it's gone.
2 used to express contemptuous dismissal: “Oh, poof!” said Will. “You say that every year.”

thud |THəd|
noun
a dull, heavy sound, such as that made by an object falling to the ground: Jean heard the thud of the closing door.

clank |klaNGk|
noun
a loud, sharp sound or series of sounds, typically made by pieces of metal meeting or being struck together: the groan and clank of a winch.

If you don't find it, you can just make something up. But include some context, or you risk not being understood:

She dropped into the chair with a plooomp.

If we hadn't been told what was happening here, we might not be able to determine what the ploomp sound signified.