Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
cham sac » cham soc, pham sach, cap sac
lang van » dang van, tang van, hoang van
hang di » hang doi, hang vi, hang dien
hanh di » hanh vi, hanh de, danh di
sac van » cac van, san van, sat van
vu cham » va cham, vu kham, tu cham
hieu vu » hieu va, hieu ve, hieu su
van hoi » van hoa, van hoc, van hoe
ky lang » ky nang, ky dang, ky tang
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sach) or (thu hoach)) ky lang van hoi. hieu vu cham sac van ((hanh di) or (hang di)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (thu hoach)) ky lang van hoi. hieu vu cham sac van ((hanh di) OR (hang di)) cua tre.
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (thu hoach)) ky lang van hoi. hieu vu cham sac van ((hanh di) or (hang di)) cua tre*.