Perhaps you should try some spelling variations:
trang thiet » trong thiet, trinh thiet, toan thiet
dung trang » dung trong, dung trung, dung thang
doi chieu » doc hieu, doi chi, mot chieu
thiet van » thien van, thi van, hieu van
phan dat » phan dau, phan dai, phan day
dat dung » dan dung, vat dung, da dung
van khan » van khanh, van khang, van phan
khan cap » khan ap, than cap, khoan cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doi chieu) OR (toc thieu)) sach - phan dat dung trang thiet van khan cap~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doi chieu) OR (toc thieu)) sach - phan dat dung trang thiet van khan cap".
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) OR (toc thieu)) sach - phan dat dung trang thiet van khan cap*.