By sending corporate gifts/complementary vouchers to customers - Can we improve our sales?

Yes, I agree, simply because building good relationships with your clients will give your business positive figure. It was like marketing your company by word of mouth, less expensive and effective.

Yes, it can make the brand more interesting to the clients as well as customes.It also can make the brand popular.

In a B2B type of market, you probably can and will improve your sales etc. 

But, in a B2C market, it will cost more than it generate and mostly will not cover its cost. As personal consumers are various and differ in many levels. 

Yes it may make them brand loyal. 

I thinks it's a main part of customer loyalty program you should build and also in some cases you can send the gift to be an advertisement for new product or as a sample of your work in all ways the cost of doing this will return for you to keep your current customer or to gain new customers 

in some cases such as penetration stage of any brand or after time to make the customer loyal 

Rises customer satisfaction, that transfer him to a Repeat Customer.

An old saying goes "Gifts increases love and friendship between people" if you are going to go out of your way to go the extra mile for your customers, then when the time comes for your customers to make their next purchase they are likely to remember you and would prefer to do business with you again simply because it is all about building relationships on a level of humanity and psychologically we humans then to respond more to those who respond to us.

yes for shore we will get the benefits from that. 

Thanks 

Yes, you can and build strong customer relation 

Increase limited discount ratio beeped on purchase value per every client by member discount card increase loyalty of client, offer customer service after sales operation