Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
nam quan » nam huan, nam qua, sam quan
tinh cua » trinh cua, sinh cua, tinh chat
va thanh » gia thanh, va tinh, le thanh
cua tre » cua te, cuu tre, cua triet
sach ky » sach y, sach ty, sach kem
hieu ca » hieu cac, hieu cua, hieu va
sac ky » cac ky, sai ky
ca nam » cua nam, cai nam, ha nam
x hoi » xa hoi, o hoi, x ho

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 ky) OR (sac ky)) nang x hoi. hieu ca nam quan ((va thanh) or (ban thanh)) tinh cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang x hoi. hieu ca nam quan ((va thanh) OR (ban thanh)) tinh cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) OR (sac ky)) nang x hoi. hieu ca nam quan ((va thanh) or (ban thanh)) tinh cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) OR (sac ky)) nang x hoi. hieu ca nam quan ((va thanh) or (ban thanh)) tinh cua tre*.