Giving them pollen or pollen substitute will promote increase brood production. If honey stores are low, then supplement with sugar syrup as well.
I agree with this statement. Pollen is important for "brood" rearing, therefore a sufficient store of pollen and honey encourages the queen to lay more eggs and the hive to rear larvae. When feeding sugar during monsoon try 3/5 sugar and 2/5 water ratio. Here in my country we experience heavy rains and during those times I use the ratio I have just given. Brood rearing is essential before the main honey flow, as the hive needs a lot of forager bees.