Perhaps you should try some spelling variations:
hanh tai » thanh tai, hang tai, han tai
van hanh » van thanh, ban hanh, van anh
sach thu » sach thue, sach thieu, sach tham
nang mai » nang ma, nang tai, lang mai
truc van » truc va, thuc van, truc ban
cuc tre » duc tre, cua tre, cuu tre
sach ky » sac ky, sach y, sach ty
mai hoi » mai khoi, dai hoi, lai hoi
va dao » ca dao

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 (sach thu)) nang mai hoi. lieu ((va dau) OR (va dao)) truc van hanh tai cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach thu)) nang mai hoi. lieu ((va dau) OR (va dao)) truc van hanh tai cuc tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sach thu)) nang mai hoi. lieu ((va dau) OR (va dao)) truc van hanh tai cuc tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach thu)) nang mai hoi. lieu ((va dau) OR (va dao)) truc van hanh tai cuc tre*.