Perhaps you should try some spelling variations:
thien van » thi van
hanh lai » hanh lam, hanh tai, thanh lap
cham tuc » nham thuc, pham thuc, tham thuc
van cham » van chat, van tham, va cham
nang cau » nang cao, hang cau, nang dau
sach ky » sach y, sach ty, sach kem
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
tuc va » thuc va, truc va, tuc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach ky) OR (sac ky)) nang cau hoi. thien van cham tuc va ((hanh lai) or (hanh vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (sac ky)) nang cau hoi. thien van cham tuc va ((hanh lai) OR (hanh vi)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) OR (sac ky)) nang cau hoi. thien van cham tuc va ((hanh lai) or (hanh vi)) cua tre".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) OR (sac ky)) nang cau hoi. thien van cham tuc va ((hanh lai) or (hanh vi)) cua tre*.