Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thuc dan » thuc hanh, hoc dan
hanh tri » thanh tri, hanh tai, hanh trinh
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
va nam » van nam, ha nam, va nay
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: toc sach ky lang xa hoi. lieu va nam ((thuc vat) or (thuc dan)) hanh tri cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky lang xa hoi. lieu va nam ((thuc vat) OR (thuc dan)) hanh tri cua tu.
• Adding a wildcard symbol may retrieve word variants: toc sach ky lang xa hoi. lieu va nam ((thuc vat) or (thuc dan)) hanh tri cua tu*.