Perhaps you should try some spelling variations:
trinh tai » trinh toan, trinh tu, trinh han
sach thu » sach thue, sach thieu, sach tham
tang van » dang van, hoang van, trong van
tai cua » thai cua, tai cuc, tri cua
luc lap » luc lam, tuc lap, luc luan
cam luc » cam xuc, cau luc
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
sach ty » sach y, sach tu, xach tay
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ty) OR (sach thu)) ((tang van) or (lang xa)) hoi. hieu va cam luc lap trinh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach thu)) ((tang van) OR (lang xa)) hoi. hieu va cam luc lap trinh tai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) OR (sach thu)) ((tang van) or (lang xa)) hoi. hieu va cam luc lap trinh tai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) OR (sach thu)) ((tang van) or (lang xa)) hoi. hieu va cam luc lap trinh tai cua tre*.