Perhaps you should try some spelling variations:
cham duc » pham duc, cham soc, pham duy
sach tu » sach thu, cach tu, sach uu
tinh va » tich va, trinh van, trinh vat
va tinh » may tinh
su cham » su pham, tu cham, vu cham
hieu su » hieu sau, tieu su, hieu so
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
sach ty » sach y, sach thu, xach tay
va chu » va che, va cau, va chi
chu te » chu de, chu tu

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 tu) OR (sach ty)) ((nang xa) or (lang xa)) hoi. hieu su cham duc va tinh va chu te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach tu) OR (sach ty)) ((nang xa) OR (lang xa)) hoi. hieu su cham duc va tinh va chu te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach tu) OR (sach ty)) ((nang xa) or (lang xa)) hoi. hieu su cham duc va tinh va chu te".
• Adding a wildcard symbol may retrieve word variants: su ((sach tu) OR (sach ty)) ((nang xa) or (lang xa)) hoi. hieu su cham duc va tinh va chu te*.