Perhaps you should try some spelling variations:
cac truc » cau truc, cac tru, cac trung
su triet » su viet, ve triet
hang don » hang ton, hang doi, dang don
van hang » van khang, van hoang, van thang
truc van » truc va, thuc van, truc ban
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
vu nang » vuc nang, va nang, vu dang
su tien » su kien, su hien, tu tieng
v nang » va nang, van nang, voi nang

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ((v nang) or (vu nang)) xa hoi. hieu va cac truc van hang don ((su triet) OR (su tien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((v nang) OR (vu nang)) xa hoi. hieu va cac truc van hang don ((su triet) OR (su tien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((v nang) or (vu nang)) xa hoi. hieu va cac truc van hang don ((su triet) OR (su tien))".
• Adding a wildcard symbol may retrieve word variants: su sach ((v nang) or (vu nang)) xa hoi. hieu va cac truc van hang don ((su triet) OR (su tien))*.