Perhaps you should try some spelling variations:
ban hanh » ban hang
hanh ca » hanh cac, hanh cat, hanh cua
sach ty » sach y, sach tu, sach thu
duc ban » duc tan, duc van, dua ban
sanh ty » canh tay
ca cua » co cua
ve cam » ve cham, ve cac, va cam
xang o » lang o, tang o, dang o
cua te » cua tu
va co » vo co
o hoc » co hoc, mo hoc, so hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: so ((sanh ty) OR (sach ty)) xang o hoc. hieu ((ve cam) or (va co)) duc ban hanh ca cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so ((sanh ty) OR (sach ty)) xang o hoc. hieu ((ve cam) OR (va co)) duc ban hanh ca cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so ((sanh ty) OR (sach ty)) xang o hoc. hieu ((ve cam) or (va co)) duc ban hanh ca cua te".
• Adding a wildcard symbol may retrieve word variants: so ((sanh ty) OR (sach ty)) xang o hoc. hieu ((ve cam) or (va co)) duc ban hanh ca cua te*.