Perhaps you should try some spelling variations:
trinh mang » trinh bang, trinh nang, trinh giang
trinh vang » trinh van, trinh bang, trinh nang
cua viet » ca viet, hoa viet, cua vat
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
hieu ve » hieu va, hieu van
ve nam » he nam, va nam, le nam
nam tu » nam thu, nam thuc
x hoi » xa hoi, o hoi, x ho

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 ty nang x hoi. hieu ve nam tu duy ((trinh vang) OR (trinh mang)) cua viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty nang x hoi. hieu ve nam tu duy ((trinh vang) OR (trinh mang)) cua viet".
• Adding a wildcard symbol may retrieve word variants: su sach ty nang x hoi. hieu ve nam tu duy ((trinh vang) OR (trinh mang)) cua viet*.