Dhuhoom is not a common English word. It is possible that it is a transliteration of an Arabic word, such as ضحوم (pronounced "dhuhoom"). This word has several meanings in Arabic, including:
Noisy
Uproarious
Tumultuous
Chaos
Utter confusion
It could also be a transliteration of a word from another language, such as Hebrew or Urdu. However, without more context, it is difficult to say for sure what dhuhoom means in English.
If you can provide more information about the context in which you heard or saw this word, I may be able to give you a more specific answer.