Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
dieu cua » dieu tra
sach vu » sach va, sach tu, sach uu
vu nang » vuc nang, va nang, vu dang
nang xa » nang x, lang xa, nang ma
van hau » van ha, van hai, van dau
hau duc » huu duc, ha duc, pham duc
duc van » duc va, duc tan, duc manh
de cua » le cua, te cua

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 vu nang xa hoi. hieu van hau duc van hanh ((de cua) or (dieu cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach vu nang xa hoi. hieu van hau duc van hanh ((de cua) OR (dieu cua)) tre.
• Adding a wildcard symbol may retrieve word variants: toc sach vu nang xa hoi. hieu van hau duc van hanh ((de cua) or (dieu cua)) tre*.