Clearly the poll under-represented the voices of the poor and ethnic minorities in Vietnam. Hence with serious precaution, here are some quick thoughts to share:
1. Financing may be not the biggest problem.
2. The other three options imply that low social returns to economic activities may be the biggest problem. I am currently working on this hypothesis!
3. Except Ho Chi Minh City where people are in generally more isolated with ethnic minority, results in other three provinces reflected other things may be the problems that deserved examination. For example: there is lack of entrepreneurship among the indigenous poor.
You may have been already aware of the fact that although social welfare is available for the indigenous poor, there are huge differences in quality as well as quantity between rural/urban or highland/lowland.
Everything is still speculation at best, please share with us new evidences from your researches as soon as you have them.