Perhaps you should try some spelling variations:
tinh voi » trinh voi, tinh doi, binh voi
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
cac dai » cac dan, cac bai, can dai
tinh vi » trinh vi, tinh va, dinh vi
ve cac » va cac, vien cac
dai va » mai va
x hoi » xa hoi, o hoi, x ho
thiet » thieu

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 cac dai va ((tinh vi) OR (tinh voi)) va thiet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty nang x hoi. hieu ve cac dai va ((tinh vi) OR (tinh voi)) va thiet".
• Adding a wildcard symbol may retrieve word variants: su sach ty nang x hoi. hieu ve cac dai va ((tinh vi) OR (tinh voi)) va thiet*.