It's not like (clause)

This phrase basically means that a statement is not true. In the example above, the statement "we need some more food" is not true.

You use "it's not like ___" when you want to give a reason for doing or not doing something. For example, if you're trying to convince your parents to let you borrow their car for the weekend, you can say:

It's not like I'm a bad driver or anything.

For another example, if a family member is telling you not to eat fast food, you can say:

It's not like I eat fast food all the time.

not...any

You use the word "any" in a negative sentence, with "not":

We don't have any laundry detergent left.

There aren't any good restaurants around here.

In a positive sentence, you use "some" instead:

We have some laundry detergent.

There're some good restaurants around here.