In order to follow any strategy in Blackjack you have to understand how Blackjack is played and what the purpose of strategies are.  All strategies in gambling are meant to help you get the upper hand in whatever game it is that you are playing at that moment.  You should not attempt a strategy if you have not mastered the technique of playing Blackjack.  There are different ways in which to play Blackjack and there are also a lot of different games that relate back to the original Blackjack game.

Putting it simply, using a hard hand strategy in your game of Blackjack just means that there are no aces available for you to play.  Considering that your ideal total in the game of Blackjack is 21, you will do well to play a hard hand strategy on 8 cards on less. There is a chart that is usually available on the internet to help you work out a strategy that you feel would work for you.

Read up as much as you can on Blackjack strategies and have someone that is experienced in gambling explain the tactics to you so that you will be able to understand exactly what it is you need to do to beat the house edge when you are playing the game. Always keep in mind that if you do not know what you are doing and you just play Blackjack without any kind of strategy, you will make uneducated decisions when it comes to betting and you will end up losing badly and the casino will just make a lot of money out of you!
It seems that playing the hard hand strategy with cards of 8 or less is a very good idea if you are still inexperienced in  the game of Blackjack.  You can still request a card from the dealer if you have less than 8 cards on the table.  Even if the outcome of your game is not that good you can only improve from that total upwards and not lose too much money.