Perhaps you should try some spelling variations:
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
dau thi » cau thi, dan thi, dao thi
cuu tre » cau tren, cau treo
cua tre » cua te, cua triet, dua tren
ma hoi » mai hoi, xa hoi, ma hoa
dac va » duc va, dat va, dai va

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 ky nang ma hoi. lieu va cac ((dac va) or (day va)) dau thi ((cuu tre) OR (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ma hoi. lieu va cac ((dac va) OR (day va)) dau thi ((cuu tre) OR (cua tre))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang ma hoi. lieu va cac ((dac va) or (day va)) dau thi ((cuu tre) OR (cua tre))*".