Perhaps you should try some spelling variations:
tinh doi » trinh doc, trinh do, tinh hoc
cau tren » cu tren, dau tren, ca tren
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
sach ky » sac ky, sach y, sach kem
tinh di » trinh di, tinh da, tin di
cam luc » cam xuc, cau luc
va cam » va cham, va cac, va cao
luc va » duc va, tuc va, loc va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((sach ky) OR (sach ty)) nang xa hoi. lieu va cam luc va ((tinh di) or (tinh doi)) cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((sach ky) OR (sach ty)) nang xa hoi. lieu va cam luc va ((tinh di) OR (tinh doi)) cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((sach ky) OR (sach ty)) nang xa hoi. lieu va cam luc va ((tinh di) or (tinh doi)) cau tren".
• Adding a wildcard symbol may retrieve word variants: hoc ((sach ky) OR (sach ty)) nang xa hoi. lieu va cam luc va ((tinh di) or (tinh doi)) cau tren*.