Perhaps you should try some spelling variations:
sach ty » sach tu, sach thu, xach tay
nang du » nang tu, nang luc, nang doc
hieu ve » hieu va, hieu van
va hanh » van hanh, va thanh, va danh
tai cua » thai cua, tai cuc, dai cua
du hoi » du hoc, lu hoi, di hoi
ve cam » ve cham, ve cac, va cam
cam tu » cam thu, nam tu, dam tu

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 y) or (sach ty)) nang du hoi. hieu ve cam tu va hanh ((tai cua) or (tri cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach y) OR (sach ty)) nang du hoi. hieu ve cam tu va hanh ((tai cua) OR (tri cua)) tre.
• Adding a wildcard symbol may retrieve word variants: su ((sach y) or (sach ty)) nang du hoi. hieu ve cam tu va hanh ((tai cua) or (tri cua)) tre*.