• 2 Economic conditions
• 1 Caves
• 1 Description and travel
• 1 Environmental protection
• 1 Environmentalists
• 1 Poverty
• 1 Tourism
• 1 Welfare economics

• 1 Arvelo, Eladio
• 1 Bullfrog Films
• 1 Eclectic Aspirations (Organization)
• 1 Evans, Alastair
• 1 Films Media Group
• 1 Films for the Humanities & Sciences (Firm)
• 1 Haq, Shareef
• 1 Marlovski Media (Firm)
• 1 Network Ireland Television

• 3 English
• 1 Vietnamese

• 1 Developing countries
• 1 Sơn Đoòng Cave (Vietnam)

• 2 Documentary films
• 1 Educational films
• 1 Feature films
• 1 Internet videos
• 1 Nonfiction films
• 1 Video recordings for the hearing impaired
• 1 Videorecording

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