Perhaps you should try some spelling variations:
sach tham » sach nha
vat hanh » vat thanh, van hanh, va hanh
sach thu » sach thue, sach thieu, cach thuc
vu kham » vu khanh
hanh va » hang va, hanh vi
hoc vat » hoc va, hoc viet, thuc vat
tu cham » toc cham, thi cham
xang xa » lang xa, mang xa, ang xa
va cua » va chua, via cua, ca cua
cua tu » cua tuc, cua su, cua cu

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 thu) or (sach tham)) xang xa hoi. hieu ((tu cham) or (vu kham)) hoc vat hanh va cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach thu) OR (sach tham)) xang xa hoi. hieu ((tu cham) OR (vu kham)) hoc vat hanh va cua tu.
• Adding a wildcard symbol may retrieve word variants: tu ((sach thu) or (sach tham)) xang xa hoi. hieu ((tu cham) or (vu kham)) hoc vat hanh va cua tu*.