Perhaps you should try some spelling variations:
yemen developpement » yemen development, en developpement, de developpement
data communication » data communications
developpement de » developpement des, developpement durable
technology 2.1 » technology 2.2, technology 3.1, technology 1
2.1 inflation » 2.3 inflation, 2.3.1 inflation, 2 inflation
de afrique » de l'afrique, en afrique, l afrique
rate base » rate band, rate bias, rate baskets
base data » based data, case data, basic data

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

• Adding a wildcard symbol may retrieve word variants: technology 2.1 inflation rate base data communication costs yemen developpement de afrique.*.