Spin education/scouting is the key problem.
Heres an interesting little thought from Piyal Wijetunge (Who was almost snapped up by BCB); he is in charge of identifying and grooming spinners in Sri Lanka.
When it comes to raw spinners, the ability, dexterity at turning the ball, to send it whirring, revving through the air or off the ground, is innate. Like timing is with batsmen. Much can be trained, but the talent of spinning the ball? "Boys are born with that talent. Between 15 and 19, they learn the skills."
http://www.espncricinfo.com/magazine...ry/927879.html
Here is what Raju had to say
“There is already skill available. We are just asking them to be a little more relaxed and work on getting more variations on the ball. If you see, most of the bowlers often forget to put in more revolutions on the ball.
“They just try to bowl quicker and quicker and then finish their four overs and go. We basically want them to have more variations without changing their actions,” said Raju, adding that the habit of putting in more revolutions will help Bangladesh's spinners extract more turn when they go abroad and play on wickets that don't suit spinners.
http://www.thedailystar.net/sports/c...e-spin-1270786
I have first hand experience with veteran coaches who encourage their students to beat batsmen in air, bowl accurately. they shun youngsters trying to get the ball to rip. Even coaches from domestic teams ask bowlers to bowl accurately, as giving air can lead to a few long hops.
First thing BCB needs to do is hire a full time spin coach. Get Raju if possible. Get the person to work with academy and national team players on full time basis. One week of coaching wont get you anywhere.