Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
hanh thai » nhanh thai, hinh thai, hanh tai
duc manh » suc manh, duc minh, duc tan
thai cua » than cua, tai cuc, tri cua
sach ky » sac ky, sach ty, sach kem
nang ro » nang co, nang ho, nang ra
cua tre » cua te, cuu tre, cua triet
ro hai » co hai, o hai, so hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: te ((sach ky) or (sach y)) nang ro hai. hieu hien dai ((duc manh) OR (duc anh)) hanh thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ky) OR (sach y)) nang ro hai. hieu hien dai ((duc manh) OR (duc anh)) hanh thai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ky) or (sach y)) nang ro hai. hieu hien dai ((duc manh) OR (duc anh)) hanh thai cua tre*".