| Accounting | 33 |
| Accumulators | 7 |
| Acridology | 8 |
| Agriculture | 2069 |
| Animal husbandry | 103 |
| Antennas and waveguides | 80 |
| Art | 8 |
| Astronautics | 11 |
| Automated equipment | 51 |
| Automatic control | 32 |
| Aviation | 6 |
| Banking | 7 |
| Beekeeping | 1 |
| Biochemistry | 3 |
| Biology | 2 |
| Biotechnology | 13 |
| Book binding | 6 |
| Botany | 21 |
| Brewery | 1 |
| Business | 29 |
| Cables and cable production | 13 |
| Canada | 17 |
| Cartography | 2 |
| Chemical fibers | 16 |
| Chemistry | 664 |
| Cinematography | 10 |
| Climatology | 1 |
| Coal | 74 |
| Commerce | 89 |
| Communications | 1438 |
| Computer networks | 6 |
| Computer numerical control | 23 |
| Computers | 2 |
| Construction | 437 |
| Corporate governance | 49 |
| Criminal law | 43 |
| Cultural studies | 56 |
| Customs | 24 |
| Data processing | 41 |
| Demography | 14 |
| Dyalysis | 18 |
| Dyes | 7 |
| Earth sciences | 401 |
| Ecology | 5 |
| Economics | 756 |
| Education | 159 |
| Electric machinery | 8 |
| Electric motors | 16 |
| Electric traction | 24 |
| Electricity generation | 18 |
| Electrochemistry | 4 |
| Electronics | 1538 |
| Employment | 1 |
| Energy industry | 107 |
| English | 5 |
| Entomology | 2 |
| Environment | 663 |
| European Union | 2 |
| Finances | 1299 |
| Fish farming pisciculture | 131 |
| Fishery fishing industry | 60 |
| Food industry | 133 |
| Food service and catering | 49 |
| Forestry | 199 |
| Gardening | 2 |
| General | 2342 |
| Genetics | 30 |
| Geography | 8 |
| Geology | 5 |
| Government, administration and public services | 7 |
| Health care | 353 |
| Hobbies and pastimes | 50 |
| Horticulture | 33 |
| Human rights activism | 66 |
| Hydrology | 45 |
| Hygiene | 1 |
| Ichthyology | 13 |
| Immigration and citizenship | 84 |
| Industry | 897 |
| Information technology | 1098 |
| Insurance | 161 |
| International law | 5 |
| International Monetary Fund | 675 |
| International trade | 34 |
| Investment | 11 |
| Isolation | 14 |
| Knitted goods | 3 |
| Labor law | 105 |
| Labor organization | 21 |
| Laboratory equipment | 25 |
| Latin American | 1 |
| Law | 985 |
| Leather | 17 |
| Librarianship | 33 |
| Life sciences | 326 |
| Lighting other than cinema | 6 |
| Loading equipment | 24 |
| Magnetics | 14 |
| Marketing | 147 |
| Materials science | 312 |
| Mathematics | 106 |
| Measuring instruments | 58 |
| Mechanic engineering | 526 |
| Medical | 972 |
| Metallurgy | 560 |
| Mexican | 14 |
| Microbiology | 10 |
| Microsoft | 500 |
| Milk production | 52 |
| Mineral products | 16 |
| Mineralogy | 1 |
| Mining | 1 |
| Municipal planning | 20 |
| Name of organization | 649 |
| Natural resourses and wildlife conservation | 17 |
| Natural sciences | 323 |
| Nautical | 2 |
| Nuclear and fusion power | 8 |
| Nuclear physics | 38 |
| Obsolete / dated | 23 |
| Oil / petroleum | 6 |
| Packaging | 359 |
| Paint, varnish and lacquer | 1 |
| Patents | 619 |
| Pest control | 34 |
| Pharmacology | 1 |
| Pharmacy and pharmacology | 45 |
| Photography | 5 |
| Physical sciences | 12 |
| Physics | 6 |
| Piezoelectric crystals | 15 |
| Plastics | 4 |
| Politics | 268 |
| Polygraphy | 2 |
| Polymers | 6 |
| Power electronics | 14 |
| Power lines | 40 |
| Power system protection | 5 |
| Private international law | 1 |
| Procedural law | 34 |
| Pulp and paper industry | 7 |
| Radio | 42 |
| Radiology | 3 |
| Rail transport | 12 |
| Reliability | 12 |
| Religion | 3 |
| Remote sensing | 44 |
| Research and development | 17 |
| Resins | 3 |
| Satellite communications | 3 |
| School | 25 |
| Scientific | 25 |
| Security systems | 21 |
| Semiconductors | 11 |
| Social science | 197 |
| Socialism | 11 |
| Sociology | 10 |
| Soil science | 67 |
| Sound recording | 10 |
| Spanish | 22 |
| Statistics | 362 |
| Sugar production | 1 |
| Superconductivity | 20 |
| Taxes | 68 |
| Technology | 243 |
| Telecommunications | 29 |
| Telegraphy | 19 |
| Telephony | 2 |
| Textile industry | 237 |
| Thermal Energy | 18 |
| Tobacco industry | 2 |
| Trade unions | 4 |
| Transformers | 4 |
| Transport | 1920 |
| United Nations | 802 |
| Vacuum tubes | 5 |
| Veterinary medicine | 8 |
| Video recording | 2 |
| Virology | 1 |
| Waste management | 12 |
| Water resources | 192 |
| Water supply | 7 |
| Welding | 5 |
| Welfare & Social Security | 4 |
| Wind Energy | 2 |
| Wood processing | 39 |
| Work flow | 92 |
