Perhaps you should try some spelling variations:
nuoc sach » nguoi sach, hoc sach, cuoc cach
doc sach » hoc sach, toc sach, dac sac
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
tai cua » thai cua, tai cuc, tri cua
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
ly nang » ky nang, ly hang, ly vang
cua tre » cua te, cuu tre, cua triet
ve dat » de dat, va dat, ve dao

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((nuoc sach) or (doc sach)) ly nang ma hoa. hieu ve dat nuoc ((van hanh) or (ban hanh)) tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((nuoc sach) OR (doc sach)) ly nang ma hoa. hieu ve dat nuoc ((van hanh) OR (ban hanh)) tai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((nuoc sach) or (doc sach)) ly nang ma hoa. hieu ve dat nuoc ((van hanh) or (ban hanh)) tai cua tre*.