Perhaps you should try some spelling variations:
trinh vat » trinh van, trinh luat, sinh vat
su sach » so sach, vu sach
tinh va » tich va, trinh van, tinh gia
coc tuc » coc luc, hoc thuc, doc thuc
hieu ve » hieu va, hieu van
ky tang » ky nang, ky dang, kho tang
ky lang » ky nang, ky dang, tay lang
cua tre » cua te, cuu tre, cua triet
ve coc » ve cuoc, ve cac, ve co
tuc va » thuc va, truc va, tuc xa

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 ((ky lang) or (ky tang)) xa hoi. hieu ve coc tuc va ((tinh va) OR (trinh vat)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ky lang) OR (ky tang)) xa hoi. hieu ve coc tuc va ((tinh va) OR (trinh vat)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ky lang) or (ky tang)) xa hoi. hieu ve coc tuc va ((tinh va) OR (trinh vat)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ((ky lang) or (ky tang)) xa hoi. hieu ve coc tuc va ((tinh va) OR (trinh vat)) cua tre*.