Nevertheless I only can search for one gene at a time, in MapViewer, for that reason I am asking you if is there any software for searching several genes and watch them at the same time in the same map?
The shortcoming here is that even if we could search for two (or more genes) at a single time (e.g. geneA AND geneB) they could fall on different chromosomes. How would they be represented in one single figure? I don't know any browser that can allow for that. However if you have a list of gene names such as BRCA2, DMD, SRY, BRAF, you can attach that list to the Ensembl browser for example and view them (they would be features) on the karyotype. Check 'Use my own data in Ensembl' tutorial page and check this image for more details.
GenomeGraphs could be worthwhile investigating...