Perhaps you should try some spelling variations:
hanh day » hanh may, hanh dao, thanh dat
nang tai » hang tai, tang tai, sang tai
tai khoa » da khoa, noi khoa
so sach » so sanh, bo sach, co sach
cua tre » cuu tre, cua triet, dua tren
han day » phan day, han dau, dan day
sach ky » sac ky, sach y, sach ty
cac luc » cau luc, coc luc, cac nuoc
hieu ve » hieu va, hieu van
luc va » duc va, tuc va, loc va
ve cac » va cac, vien cac
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ky nang tai khoa. hieu ve cac luc va ((hanh day) OR (han day)) ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang tai khoa. hieu ve cac luc va ((hanh day) OR (han day)) ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ky nang tai khoa. hieu ve cac luc va ((hanh day) OR (han day)) ((cua tre) or (cua te))".
• Adding a wildcard symbol may retrieve word variants: so sach ky nang tai khoa. hieu ve cac luc va ((hanh day) OR (han day)) ((cua tre) or (cua te))*.