Fertilizer is vastly overrated and intended only for indoor plants that have been in the same pot for a year or more, are healthy and are growing vigorously. It is not medicine to cure problems and it will not make plants grow bigger or faster.
The product you ordered is no better or worse than most other products. Use it only for plants that are growing as I described above. Plants growing in low light do not need any fertilizer.
For those that do, dilute it to half-strength and apply it no more than once per month and only when they are growing.
There are lots of things to consider when caring for indoor plants, but fertilizer is not high on the list.