y not pay them more like u do to other job categories and encourage them to come here.. one last thing... show an advertisement or an job in classifieds for a blue collar job in the western media, be it any media ... like how its advertised in the other part of the world... more money is always a good bargain....

giving u an example below... read carefully....

converstion rate western currency 1 = GCC 4

western manager in GCC paid 50k/m approx.annually would be 600k,when converted, this would be 150k, but the same in their home country would be getting nothing more than 100k. so apply the same logic and get the labourers...
give them more salary....entice them...

finally, show me an advertisement calling for recruitment of labourers and promising them higher salary....

i bet u will never get it...