I had 20000dollers stolen can i deduct this from my taxes

A theft loss can be included in the Casualty and Theft Loss itemized deduction on Schedule A.  Theft losses must be reduced by $100 plus 10% of your adjusted gross income.  So if you AGI is $21,000 or higher, you won't be able to take this loss.

Deductions such as medical expenses, charitable contributions, mortgage interest, property taxes, state and local income or sales taxes, casualty and theft losses and others are what is known as “itemized deductions”.  You can see a more complete list of all these deductions, at least the most common, by looking at Schedule A of Form 1040.  They are used to reduce your taxable income.  The total of all your itemized deductions must exceed your standard deduction to be of any tax benefit.  Anyone filing a Federal income tax return (other than children under the age of 24 with unearned income) is entitled to the standard deduction.  The standard deduction for 2016 is $6,300 Single and $12,600 Married Filing Jointly.