Perhaps you should try some spelling variations:
coc truc » hoc truc, cau truc, hoc thuc
sach ky » sac ky, sach y, sach kem
tinh va » tich va, trinh van, trinh vat
va tinh » may tinh
truc va » thuc va, thuc vat, trung va
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu van
dang xa » dang xay, lang xa, dang ha
sach ty » sach y, sach tu, sach thu
va cua » va chua, via cua, ca cua

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