Perhaps you should try some spelling variations:
communication cost » communication costs, communication costa, communications costs
models development » model development, module development, model developments
4.1 communication » 4 communication, 2.3 communication, 3.2 communication
technology help » technologies help, technology how, technology human
help inflation » high inflation, der inflation, bei inflation
development en » developpement en, development menu, development eco
cost models » cost model, logit models
rate date » rate data, trade date, rate water
date 4.1 » daten 4.1, data 4.1, date 4.2

You may be able to get more results by adjusting your search query.

• Adding a wildcard symbol may retrieve word variants: technology help inflation rate date 4.1 communication cost models development en afrique.*.