Kamal, did you read this article on Net-http://www.emedicinehealth .com/ticks/article_em.htm?
When you catch ticks, make sure you 'completely' get rid of them. When I brought my dog he was heavily infected by them and I'd collect all ticks I come across in a box and then at the end of day I would wrap them on a newspaper and burn it off! cruel though, but these ticks can come back or target another host if simply thrown out of the house.
The encouraging sign is that ticks have started to 'leave' the host ( your dog ) and have started to search another host. Tick can potentially carry disease just like mosquitos and cockroaches. If any case you feel that ticks are everywhere in house, walls, bed, floor, water, etc call pest control agencies. I know some prominent ones and mentioning the links: