Portfolio suggestions pharma/agri/cement

Investment depends upon whether if your are risk averse or a speculator. Some include government bonds in their portfolios to reduce risk. Some invest in equity like you are planning as a long term trade because, equity is volatile in the short term. There other things which investors analyse; minimum returns for a given risk and maximum returns for a given volatility. 

Many traders have access to softwares and they can analyse things better.  Or else, use Markowitz portfolio optimisation for individual stocks and plot efficient frontiers to interpret which portfolio curves the  top position. The Covarianse analysis in Markowitz model will let you know which stocks are trading in the opposite directions, which ones are going in the same direction which will help you to decide eliminating unwanted stock. This is time consuming for a beginner, but you will get your results.