Ac blows very little cold air

Was it blowing colder air before or has it always been this way

First make sure you have a clean filter, next be sure return air vents are not closed or blocked
If all if OK, you might try spraying out the condenser coil ,with power turned off from the inside out,the sometimes get clogged up with tree pollen and grass clippings. Yhe evaporater coil could be stopped up but a little tricky doing this unless you know what you are doing and you have the right cleaner to do it with,, thy all these you can and let us know what you have improved