For a non-U.S. citizen, you will be deported for any drug offense conviction, other than one (1) misdemeanor incident of Possession of Marijuana < 1 Ounce, and will never be lawfully admitted to the U.S. again. Even one (1) misdemeanor < 1 Ounce conviction will make you inadmissible to the U.S. upon re-entry. Only some will qualify for a waiver of inadmissibility.
You need an experienced CrImmigration Attorney to overcome your charges. Potential defenses may include suppression of evidence obtained in violation of your 4th Amendment Right to be free of Unlawful Search and Seizure. This requires a deep knowledge of the law and police practices.