Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
van hac » van hoc, van ha, van hai
thi cuu » thi cuc, thi huu, thi cu
dau thi » cau thi, dan thi, dao thi
sach ky » sac ky, sach y, sach ty
van cac » van cau, van bac, dan cac
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
cuu tre » cua tre, cau tren, cau treo
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa

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 ky lang xa hoi. hieu ((van cac) or (van hac)) ((xuc va) OR (tuc va)) dau thi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky lang xa hoi. hieu ((van cac) OR (van hac)) ((xuc va) OR (tuc va)) dau thi cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky lang xa hoi. hieu ((van cac) or (van hac)) ((xuc va) OR (tuc va)) dau thi cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky lang xa hoi. hieu ((van cac) or (van hac)) ((xuc va) OR (tuc va)) dau thi cuu tre*.