Since most Vietnamese words are composed of more than one syllable where each syllable is separated by blanks (Dinh et al., 2008), using common tokenizers such as replacing blanks with word boundaries does not work for Vietnamese.
the CRFbased tool of the group (Tu et al., 2006), the PVnSeg tool (unknown source) and the hybrid method of (Hong Phuong et al., 2008) are compared using a test corpus containing 1,264 articles from Politics-Society section of a Vietnamese online newspaper "Tuoi Tre", where words have been manually segmented by linguists.