How to improve the lawn gr and make it more dense.hyderabad india.?

i have a 400sqft lawn.with courier gr.recently the gr was cut using a manual lawn mover for the first time since it was put last year in december 2006.good amount of water,fertliser is put.have a gardener doing the watering and stuf.but the lawn is not lush and dense.it has small patches of ground and white gr is there.it is in partiallyshaded area with some tree cover over it.was the gr choice wrong.if have number for some profesional who can look at my lawn,feel free to give me number.