Perhaps you should try some spelling variations:
dan tren » dat tren, dau tren, van tren
sach ty » sach y, sach tu, sach thu
cao hoc » co hoc, cho hoc, chat hoc
sach ky » sac ky, sach y, sach kem
vu cham » va cham, vu kham, tu cham
va hanh » van hanh, va thanh, va danh
hanh ke » hanh kem, thanh ke, hanh ky
ve cham » va cham, ve chat, ve chim
xuc va » duc va, tuc va, luc va
ke dan » le dan

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach ky) OR (sach ty)) nang cao hoc. hieu ((ve cham) or (vu cham)) xuc va hanh ke dan tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (sach ty)) nang cao hoc. hieu ((ve cham) OR (vu cham)) xuc va hanh ke dan tren*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) OR (sach ty)) nang cao hoc. hieu ((ve cham) or (vu cham)) xuc va hanh ke dan tren*".