Perhaps you should try some spelling variations:
oral communication » personal communication
variation des » variation _, variation 6, variation series
des fabrique » la fabrique, des briques
topologie 1 » topologie 2, topologie 3, topologie 4
1 variation » 1 variations, _ variation, 2 variation
des ddr » der ddr, des dr, dem ddr
3 des » 3 der, 3 das, _ des
a des » a der, a das

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "topologie 1 variation des ddr oral communication ((3 des) OR (a des)) developpement des fabrique.~".
• Adding a wildcard symbol may retrieve word variants: topologie 1 variation des ddr oral communication ((3 des) OR (a des)) developpement des fabrique.*.