The 20c and 5c stamp on the top are from 2005 Occupations issue illustrating shoemaker and seamstress.
The 10c stamp is from 2002 Musical Instruments issue showing Trumpet.
The 1R stamp is from 2008 Animals in Amazon issue featuring Amazonian Manatee (Trichechus inunguis) which is a species of manatee that lives in the freshwater habitats of the Amazon basin.
They are found in Brazil, Peru, Colombia, Ecuador, Guyana and Venezuela. Amazonian manatees are aquatic animals of the Sirenia order and are also known as "seacows". Their colour is gray but sometimes appears to be a brownish gray. They have thick, wrinkled skin, are almost hairless but have "whiskers" around their mouths. It lacks significant predation, other than being occasionally hunted by humans. The manatees, and the closely related Dugong, are unusual in being the only plant-eating marine mammals of modern times.
A somewhat unique feature (amongst mammals) of the manatee is the constant replacement of molar teeth; new teeth enter at the back of the jaw and replace old and worn teeth at the front. Their closest cousins, the elephants also have teeth that get replaced, but have only a limited set of these replacement teeth.