Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
hieu ve » hieu va, hieu van
cau tuc » cau truc, cau tu, cau luc
tuc may » truc may, tu may, tuc xay
tinh di » tinh doi, trinh di, tinh da
cua tre » cua te, cuu tre, dua tren

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 ty nang x ho. ((hieu ve) or (hieu qua)) cau tuc may tinh di ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang x ho. ((hieu ve) OR (hieu qua)) cau tuc may tinh di ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty nang x ho. ((hieu ve) or (hieu qua)) cau tuc may tinh di ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: su sach ty nang x ho. ((hieu ve) or (hieu qua)) cau tuc may tinh di ((cua tre) OR (cua triet))*.