If you are using the actual sales tax method where you add up your sales tax from your receipts, you can include all purchases on which you pay the standard sales tax charged in the location where the travel occurred. You can't include special taxes, like a special hotel tax on out of town visitors, or all the special taxes on air fare. Just the standard local sales tax rate, if you can prove it.
If you are using the standard method, where the IRS gives you a sales tax allowance based on your income and where you live, then no, you can't include a vacation. There is no such thing as a "major purchase" addition to the standard method. The law specifically states that the only thing you can add to the standard method is the purchase of a motor vehicle, airplane, a home, or substantial renovation to a home.
