Perhaps you should try some spelling variations:
thuc manh » thuc hanh, thuc thanh, thuc dan
thanh lap » thanh san, phan lap, thanh hai
nam thuc » nam thuoc, am thuc, nam thu
lang van » dang van, tang van, hoang van
hieu van » hieu va, thien van, lieu va
han tai » hang tai, nhan tai, van tai
sach ty » sach tu, sach thu, xach tay
van hoi » van hoa, van hoc, van hoe
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach ty) OR (sach y)) lang van hoi. hieu van nam thuc manh ((thanh lap) or (han tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach y)) lang van hoi. hieu van nam thuc manh ((thanh lap) OR (han tai)) cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) OR (sach y)) lang van hoi. hieu van nam thuc manh ((thanh lap) or (han tai)) cua tre*".