In the Philippines, the interaction between people is probably different than it is back at home, wherever you are from.
In the Philippines specifically, and generally throughout Asia, it is important to treat people with respect. “Face” is an important concept in Asia, and you have to treat people in a way that they will not lose “face”. This is very important in your dealings with business people here. If you start building a good relationship with a businessman, and then later you blow up, treat them poorly, or simply make them lose face, they may never want to deal with you again.
Causing someone to lose face will only end up causing you trouble in the long run, so be respectful when dealing with people.
For many of us westerners, if things do not go as we hope or plan, we can tend to lose our cool and explode. We might yell at somebody, or even worse. Remember, if you are dealing with clerks in a store, even a manager, that person may not have the authority to do things differently to help you. It is often the owner of the business who is the only person who has the ability to “break the rules” and do things in the way that you want. Even though it is against our western upbringing, if you blow up and treat a person rudely, they may not want your business anymore.
So, just remember, working with a businessman here is different than it is back home. If you remain patient and respectful you will likely be able to build up a real bond between yourself and the people that you are dealing with.